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Psychedex
Sources
49
17 strong · 27 moderate · 5 weak

Studies and references cited across this article, graded by evidence strength.

Claims checked
117
57verified9partial51inconclusive

Inconclusive means the cited source neither confirms nor refutes the claim — a lower-confidence badge, not an error.

Generated
May 7, 2026 · pipeline-v5
Values approved
169/169 (100%)

Data points an editor reviewed and accepted for publication.

01

Value Provenance

Dosing

smokedtrace

FieldPublishedAI ProposedConfidence
Threshold1 mg1 mgmedium
Low2–5 mg2–5 mgmedium
Common5–15 mg5–15 mgmedium
Strong15–25 mg15–25 mgmedium
Heavy25+ mg25+ mgmedium
Editorial

Dose ranges from Grotenhermen 2003 clinical review and Spindle 2018 controlled crossover study (10mg and 25mg doses). Threshold inferred from clinical reviews noting psychoactive effects at ~1–2mg. Work-notes specify these exact ranges. Not from standardized dose-finding study with these tier labels — confidence medium.

Reasoning

Dose ranges from Grotenhermen 2003 clinical review and Spindle 2018 controlled crossover study (10mg and 25mg doses). Threshold inferred from clinical reviews noting psychoactive effects at ~1–2mg. Work-notes specify these exact ranges. Not from standardized dose-finding study with these tier labels — confidence medium.

Evidence basis: systematic_review

vaporizedtrace

FieldPublishedAI ProposedConfidence
Threshold1 mg1 mgmedium
Low2–5 mg2–5 mgmedium
Common5–15 mg5–15 mgmedium
Strong15–25 mg15–25 mgmedium
Heavy25+ mg25+ mgmedium
Editorial

Same mg ranges as smoked per work-notes, but vaporized delivers higher effective dose per mg — Spindle 2018 showed vaporized 25mg produced peak blood THC of 14.4 ng/mL vs 10.2 ng/mL smoked, with stronger subjective effects. Users should be aware that equivalent mg doses produce stronger effects via vaporization.

Reasoning

Same mg ranges as smoked per work-notes, but vaporized delivers higher effective dose per mg — Spindle 2018 showed vaporized 25mg produced peak blood THC of 14.4 ng/mL vs 10.2 ng/mL smoked, with stronger subjective effects. Users should be aware that equivalent mg doses produce stronger effects via vaporization.

Evidence basis: controlled_human_study

oraltrace

FieldPublishedAI ProposedConfidence
Threshold2 mg2 mgmedium
Low5–10 mg5–10 mgmedium
Common10–20 mg10–20 mgmedium
Strong20–50 mg20–50 mgmedium
Heavy50+ mg50+ mgmedium
Editorial

Dose ranges from Grotenhermen 2003 clinical review. Oral bioavailability 4–20% but extensive first-pass conversion to active metabolite 11-OH-THC produces qualitatively different, often more intense effects. Work-notes specify these exact ranges. High interindividual variability in oral absorption reduces confidence.

Reasoning

Dose ranges from Grotenhermen 2003 clinical review. Oral bioavailability 4–20% but extensive first-pass conversion to active metabolite 11-OH-THC produces qualitatively different, often more intense effects. Work-notes specify these exact ranges. High interindividual variability in oral absorption reduces confidence.

Evidence basis: systematic_review

intravenoustrace

FieldPublishedAI ProposedConfidence
Threshold——low
Low——low
Common2.5–5 mg2.5–5 mglow
Strong5–5 mg5–5 mglow
Heavy——low
Editorial

Only two dose levels studied in controlled research: D'Souza 2004 used 2.5mg and 5mg IV in placebo-controlled crossover design. Not a recreational ROA — research setting only. Work-notes note low confidence with only 2 dose levels studied. Threshold, light, and heavy tiers not proposed due to insufficient data.

Reasoning

Only two dose levels studied in controlled research: D'Souza 2004 used 2.5mg and 5mg IV in placebo-controlled crossover design. Not a recreational ROA — research setting only. Work-notes note low confidence with only 2 dose levels studied. Threshold, light, and heavy tiers not proposed due to insufficient data.

Evidence basis: controlled_human_study

Duration

smoked

FieldPublishedAI ProposedConfidence
Onsettrace0–3 minutes0–3 minuteshigh
Editorial

Grotenhermen 2003 and Spindle 2018: inhaled THC produces effects within seconds to 3 minutes due to rapid pulmonary absorption.

Reasoning

Grotenhermen 2003 and Spindle 2018: inhaled THC produces effects within seconds to 3 minutes due to rapid pulmonary absorption.

Evidence basis: controlled_human_study

Come uptrace3–10 minutes3–10 minuteshigh
Editorial

Work-notes specify 3–10 min come-up. Spindle 2018 showed peak blood THC within 10 minutes of inhalation.

Reasoning

Work-notes specify 3–10 min come-up. Spindle 2018 showed peak blood THC within 10 minutes of inhalation.

Evidence basis: controlled_human_study

Peaktrace15–30 minutes15–30 minuteshigh
Editorial

Work-notes specify 15–30 min peak. Consistent with Grotenhermen 2003 and Spindle 2018 (blood THC peaked within 30 minutes, subjective peak similar).

Reasoning

Work-notes specify 15–30 min peak. Consistent with Grotenhermen 2003 and Spindle 2018 (blood THC peaked within 30 minutes, subjective peak similar).

Evidence basis: controlled_human_study

Offsettrace30–120 minutes30–120 minuteshigh
Editorial

Work-notes specify 30–120 min offset. Spindle 2018 showed blood THC returned near baseline within 3–4 hours.

Reasoning

Work-notes specify 30–120 min offset. Spindle 2018 showed blood THC returned near baseline within 3–4 hours.

Evidence basis: controlled_human_study

Totaltrace2–3 hours2–3 hourshigh
Editorial

Work-notes specify 2–3h total. Grotenhermen 2003 review confirms acute subjective effects duration of 2–3 hours for smoked cannabis.

Reasoning

Work-notes specify 2–3h total. Grotenhermen 2003 review confirms acute subjective effects duration of 2–3 hours for smoked cannabis.

Evidence basis: systematic_review

After effectstrace2–6 hours2–6 hourshigh
Editorial

Work-notes specify 2–6h aftereffects. Spindle 2018 showed residual cognitive effects persisting up to 6 hours post-inhalation.

Reasoning

Work-notes specify 2–6h aftereffects. Spindle 2018 showed residual cognitive effects persisting up to 6 hours post-inhalation.

Evidence basis: controlled_human_study

vaporized

FieldPublishedAI ProposedConfidence
Onsettrace0–3 minutes0–3 minuteshigh
Editorial

Same onset as smoked — Spindle 2018 showed comparable time-to-onset for vaporized and smoked routes.

Reasoning

Same onset as smoked — Spindle 2018 showed comparable time-to-onset for vaporized and smoked routes.

Evidence basis: controlled_human_study

Come uptrace3–10 minutes3–10 minuteshigh
Editorial

Work-notes specify same come-up as smoked (3–10 min). Spindle 2018 data.

Reasoning

Work-notes specify same come-up as smoked (3–10 min). Spindle 2018 data.

Evidence basis: controlled_human_study

Peaktrace15–30 minutes15–30 minuteshigh
Editorial

Work-notes specify 15–30 min peak, same as smoked. Spindle 2018.

Reasoning

Work-notes specify 15–30 min peak, same as smoked. Spindle 2018.

Evidence basis: controlled_human_study

Offsettrace30–120 minutes30–120 minuteshigh
Editorial

Work-notes specify 30–120 min offset, same as smoked. Spindle 2018.

Reasoning

Work-notes specify 30–120 min offset, same as smoked. Spindle 2018.

Evidence basis: controlled_human_study

Totaltrace2–3 hours2–3 hourshigh
Editorial

Work-notes specify 2–3h total, same as smoked. Spindle 2018.

Reasoning

Work-notes specify 2–3h total, same as smoked. Spindle 2018.

Evidence basis: controlled_human_study

After effectstrace2–6 hours2–6 hourshigh
Editorial

Work-notes specify 2–6h aftereffects. Spindle 2018 showed residual effects up to 6h.

Reasoning

Work-notes specify 2–6h aftereffects. Spindle 2018 showed residual effects up to 6h.

Evidence basis: controlled_human_study

oral

FieldPublishedAI ProposedConfidence
Onsettrace30–90 minutes30–90 minutesmedium
Editorial

Work-notes specify 30–90 min onset. Grotenhermen 2003 review. Wide range due to high interindividual variability in oral absorption.

Reasoning

Work-notes specify 30–90 min onset. Grotenhermen 2003 review. Wide range due to high interindividual variability in oral absorption.

Evidence basis: systematic_review

Come uptrace30–60 minutes30–60 minutesmedium
Editorial

Work-notes specify 30–60 min come-up. Grotenhermen 2003. Users frequently misjudge timing and redose during this phase.

Reasoning

Work-notes specify 30–60 min come-up. Grotenhermen 2003. Users frequently misjudge timing and redose during this phase.

Evidence basis: systematic_review

Peaktrace2–3 hours2–3 hoursmedium
Editorial

Work-notes specify 120–180 min peak. Grotenhermen 2003 reports peak effects at 2–3 hours.

Reasoning

Work-notes specify 120–180 min peak. Grotenhermen 2003 reports peak effects at 2–3 hours.

Evidence basis: systematic_review

Offsettrace3–8 hours3–8 hoursmedium
Editorial

Work-notes specify 180–480 min offset. Reflects slow redistribution from adipose stores and ongoing 11-OH-THC activity.

Reasoning

Work-notes specify 180–480 min offset. Reflects slow redistribution from adipose stores and ongoing 11-OH-THC activity.

Evidence basis: systematic_review

Totaltrace4–12 hours4–12 hoursmedium
Editorial

Work-notes specify 4–12h total. Grotenhermen 2003 review. Wide range reflects high interindividual variability in oral bioavailability (4–20%).

Reasoning

Work-notes specify 4–12h total. Grotenhermen 2003 review. Wide range reflects high interindividual variability in oral bioavailability (4–20%).

Evidence basis: systematic_review

After effectstrace6–24 hours6–24 hoursmedium
Editorial

Work-notes specify 6–24h aftereffects including residual sedation and cognitive fog. Prolonged terminal half-life (20–57h) drives extended aftereffects.

Reasoning

Work-notes specify 6–24h aftereffects including residual sedation and cognitive fog. Prolonged terminal half-life (20–57h) drives extended aftereffects.

Evidence basis: systematic_review

Safety

Toxicity Profiletrace

FieldPublishedAI ProposedConfidence
Acutelowlowhigh
Chronicmoderatemoderatehigh
Organs Affectedcardiovascular, pulmonary, neuropsychiatric, reproductivecardiovascular, pulmonary, neuropsychiatric, reproductivehigh
Editorial

Work-notes specify acute: low, chronic: moderate. Acute level justified by no confirmed human lethal overdose and high therapeutic index, with only minor reversible physiological effects (tachycardia, hypotension). Chronic level justified by documented psychiatric risk (psychosis OR 4.8 per Di Forti 2019), respiratory harm from combustion (Georgakopoulou 2025), and developmental toxicity (Wymore 2025). Evidence from controlled human studies (D'Souza 2004, Benowitz & Jones 1975) and large epidemiological cohorts (EU-GEI).

Reasoning

Work-notes specify acute: low, chronic: moderate. Acute level justified by no confirmed human lethal overdose and high therapeutic index, with only minor reversible physiological effects (tachycardia, hypotension). Chronic level justified by documented psychiatric risk (psychosis OR 4.8 per Di Forti 2019), respiratory harm from combustion (Georgakopoulou 2025), and developmental toxicity (Wymore 2025). Evidence from controlled human studies (D'Souza 2004, Benowitz & Jones 1975) and large epidemiological cohorts (EU-GEI).

Evidence basis: controlled_human_study

Dependence Profiletrace

FieldPublishedAI ProposedConfidence
Physicalmoderatemoderatehigh
Psychologicalmoderatemoderatehigh
Compulsive Redosinglowlowhigh
Dose Escalationmoderatemoderatehigh
Editorial

Work-notes specify physical: moderate, psychological: moderate, compulsive redosing: low, dose escalation: moderate. Supported by epidemiological data (9% CUD rate, Hasin 2017), PET neuroimaging of dopamine release (Bossong 2008), and differential tolerance findings (D'Souza 2008). Withdrawal well-characterized in Connor 2022 and Bonnet & Preuss 2017.

Reasoning

Work-notes specify physical: moderate, psychological: moderate, compulsive redosing: low, dose escalation: moderate. Supported by epidemiological data (9% CUD rate, Hasin 2017), PET neuroimaging of dopamine release (Bossong 2008), and differential tolerance findings (D'Souza 2008). Withdrawal well-characterized in Connor 2022 and Bonnet & Preuss 2017.

Evidence basis: controlled_human_study

Withdrawal Profiletrace

FieldPublishedAI ProposedConfidence
Severitymoderatemoderatehigh
Symptomsirritability, anger, aggression, anxiety, insomnia, decreased appetite, weight loss, restlessness, depressed mood, tremors, sweating, abdominal pain, headacheirritability, anger, aggression, anxiety, insomnia, decreased appetite, weight loss, restlessness, depressed mood, tremors, sweating, abdominal pain, headachehigh
FatalNoNohigh
Medical SupervisionNot requiredNot requiredhigh
Editorial

Cannabis withdrawal syndrome occurs in ~50% of regular/dependent users. Onset 24–48h, peak at 2–3 days, resolution within 1–2 weeks. Severity is mild-to-moderate; not life-threatening and does not require medical supervision. Per Connor 2022 and Bonnet & Preuss 2017.

Reasoning

Cannabis withdrawal syndrome occurs in ~50% of regular/dependent users. Onset 24–48h, peak at 2–3 days, resolution within 1–2 weeks. Severity is mild-to-moderate; not life-threatening and does not require medical supervision. Per Connor 2022 and Bonnet & Preuss 2017.

Evidence basis: controlled_human_study

Tolerance Profiletrace

FieldPublishedAI ProposedConfidence
Buildupmoderatemoderatehigh
Half-life5 days5 dayshigh
Full Reset28 days28 dayshigh
Cross-tolerancessynthetic cannabinoids, endocannabinoids, other CB1 agonistssynthetic cannabinoids, endocannabinoids, other CB1 agonistshigh
Editorial

Work-notes specify moderate buildup with 2–4 week full reset. Mechanism well-characterized via CB1 desensitization/downregulation studies (Bonnet & Preuss 2017). Differential tolerance documented in controlled IV study (D'Souza 2008). Half-life value estimated from work-notes stating 'not precisely characterized' but functional tolerance within 3–7 days.

Reasoning

Work-notes specify moderate buildup with 2–4 week full reset. Mechanism well-characterized via CB1 desensitization/downregulation studies (Bonnet & Preuss 2017). Differential tolerance documented in controlled IV study (D'Souza 2008). Half-life value estimated from work-notes stating 'not precisely characterized' but functional tolerance within 3–7 days.

Evidence basis: controlled_human_study

Effects & Profile

Contraindications

FieldPublishedAI ProposedConfidence
pregnancy breastfeeding Breastfeedingtraceabsoluteabsolutehigh
Editorial

Work-notes list breastfeeding as separate absolute contraindication. Supported by Wymore et al. 2025.

Reasoning

Work-notes list breastfeeding as separate absolute contraindication. Supported by Wymore et al. 2025.

pregnancy breastfeeding Pregnancytraceabsoluteabsolutehigh
Editorial

Work-notes list pregnancy as absolute contraindication. Supported by Wymore et al. 2025 and ACOG/AAP guidelines cited in article prose.

Reasoning

Work-notes list pregnancy as absolute contraindication. Supported by Wymore et al. 2025 and ACOG/AAP guidelines cited in article prose.

psychiatric Active psychotic disorder or personal/family history of psychotic disordertraceabsoluteabsolutehigh
Editorial

Work-notes list this as the primary absolute contraindication. Supported by D'Souza 2004 (controlled study) and Di Forti 2019 (large epidemiological study).

Reasoning

Work-notes list this as the primary absolute contraindication. Supported by D'Souza 2004 (controlled study) and Di Forti 2019 (large epidemiological study).

cardiovascular Significant cardiovascular diseasetracerelativerelativehigh
Editorial

Work-notes list as relative contraindication. Supported by Benowitz & Jones 1975 and Lucas et al. 2018.

Reasoning

Work-notes list as relative contraindication. Supported by Benowitz & Jones 1975 and Lucas et al. 2018.

respiratory Significant pulmonary disease (combustion route)tracerelativerelativemedium
Editorial

Work-notes list as relative contraindication with medium confidence. Supported by Georgakopoulou et al. 2025.

Reasoning

Work-notes list as relative contraindication with medium confidence. Supported by Georgakopoulou et al. 2025.

psychiatric Active substance use disordertracerelativerelativemedium
Editorial

Work-notes list as relative contraindication. Supported by Hasin 2017 and Hood 2018 epidemiological data.

Reasoning

Work-notes list as relative contraindication. Supported by Hasin 2017 and Hood 2018 epidemiological data.

age Adolescence (under 18)tracerelativerelativehigh
Editorial

Work-notes list as relative contraindication with high confidence. Supported by Murphy et al. 2017 and Hoch et al. 2025.

Reasoning

Work-notes list as relative contraindication with high confidence. Supported by Murphy et al. 2017 and Hoch et al. 2025.

hepatic Significant hepatic impairmenttracerelativerelativemedium
Editorial

Work-notes list as relative contraindication with medium confidence. Supported by Lucas et al. 2018 pharmacokinetic data.

Reasoning

Work-notes list as relative contraindication with medium confidence. Supported by Lucas et al. 2018 pharmacokinetic data.

other Operating vehicles or machinery while intoxicatedtracerelativerelativehigh
Editorial

Work-notes list driving as relative contraindication with high confidence. Supported by Arkell et al. 2021 and Spindle et al. 2018 (residual impairment up to 6h).

Reasoning

Work-notes list driving as relative contraindication with high confidence. Supported by Arkell et al. 2021 and Spindle et al. 2018 (residual impairment up to 6h).

Timeline Phases

smoked

FieldPublishedAI ProposedConfidence
Onsettrace0–180 sec(i=0.30)0–180 sec(i=0.30)high
Editorial

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Reasoning

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Evidence basis: controlled_human_study

Come uptrace180–900 sec(i=0.70)180–900 sec(i=0.70)high
Editorial

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Reasoning

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Evidence basis: controlled_human_study

Peaktrace900–1800 sec(i=1.00)900–1800 sec(i=1.00)high
Editorial

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Reasoning

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Evidence basis: controlled_human_study

Resolutiontrace2700–7200 sec(i=0.40)2700–7200 sec(i=0.40)high
Editorial

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Reasoning

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Evidence basis: controlled_human_study

Afterglowtrace7200–14400 sec(i=0.15)7200–14400 sec(i=0.15)high
Editorial

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Reasoning

Timeline derived from work-notes smoked phases (onset/come_up/peak/offset/afterglow). Duration values from Grotenhermen 2003 and Spindle 2018 controlled crossover study. Intensity weights from work-notes. Phase names mapped to schema: work-notes 'offset' mapped to 'resolution'. Driving advisory verbatim from work-notes.

Evidence basis: controlled_human_study

oral

FieldPublishedAI ProposedConfidence
Onsettrace1800–5400 sec(i=0.20)1800–5400 sec(i=0.20)medium
Editorial

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Reasoning

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Evidence basis: systematic_review

Come uptrace1800–3600 sec(i=0.50)1800–3600 sec(i=0.50)medium
Editorial

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Reasoning

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Evidence basis: systematic_review

Peaktrace3600–7200 sec(i=1.00)3600–7200 sec(i=1.00)medium
Editorial

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Reasoning

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Evidence basis: systematic_review

Plateautrace5400–10800 sec(i=0.80)5400–10800 sec(i=0.80)medium
Editorial

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Reasoning

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Evidence basis: systematic_review

Resolutiontrace10800–21600 sec(i=0.30)10800–21600 sec(i=0.30)medium
Editorial

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Reasoning

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Evidence basis: systematic_review

Afterglowtrace14400–43200 sec(i=0.10)14400–43200 sec(i=0.10)medium
Editorial

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Reasoning

Timeline from work-notes oral phases (onset/come_up/peak/plateau/offset/afterglow). Oral route includes plateau phase absent from inhaled due to sustained absorption and 11-OH-THC formation. Duration values from Grotenhermen 2003. Wide ranges reflect high interindividual variability in oral absorption (bioavailability 4–20%). Driving advisory verbatim from work-notes. Confidence medium due to variability.

Evidence basis: systematic_review

Dose Tier Summaries

thresholdtrace
medium

Minimal perceptible psychoactive effect. A slight mood lift and mild relaxation emerge, with a subtle alteration of sensory awareness — colours or music may seem faintly enhanced. Cognitive function remains essentially intact, though some users report a barely perceptible shift in the quality of attention. Heart rate may increase slightly. Appetite is unaffected or marginally increased. Most users at this level may question whether the dose was active at all. Functional impairment is negligible. This range is useful for gauging individual sensitivity, particularly for naive users or those returning after a tolerance break. The boundary between threshold and sub-threshold is narrow and highly individual.

Editorial

Work-notes outline threshold as minimal perceptible effect with subtle mood lift, mild relaxation, slight HR increase. Expanded with substance-specific texture from Grotenhermen 2003 and Spindle 2018 controlled study data.

Reasoning

Work-notes outline threshold as minimal perceptible effect with subtle mood lift, mild relaxation, slight HR increase. Expanded with substance-specific texture from Grotenhermen 2003 and Spindle 2018 controlled study data.

Evidence basis: controlled_human_study

lighttrace
medium

Mild euphoria and relaxation become clearly noticeable. Sensory enhancement emerges — music sounds richer, food tastes better, tactile sensations become more interesting. A subtle time distortion may be present, with minutes feeling slightly stretched. Appetite begins to increase. Cognitive effects are present but mild: a slight reduction in short-term memory efficiency and minor slowing of thought. Sociability may increase, and humour enhancement is common. Heart rate increases modestly. Dry mouth may appear. Functional impairment is mild but measurable. Most users can carry on conversation and manage routine tasks, though complex or safety-critical activities should be avoided.

Editorial

Work-notes describe mild euphoria, sensory enhancement, subtle time distortion, minor cognitive effects. Expanded from D'Souza 2004 (low-dose effects at 2.5mg IV) and Spindle 2018 (10mg smoked/vaporized).

Reasoning

Work-notes describe mild euphoria, sensory enhancement, subtle time distortion, minor cognitive effects. Expanded from D'Souza 2004 (low-dose effects at 2.5mg IV) and Spindle 2018 (10mg smoked/vaporized).

Evidence basis: controlled_human_study

commontrace
medium

A clear psychoactive state — the 'classic' cannabis experience for most users. Euphoria, sensory enhancement, appetite stimulation, and time distortion are all prominent. Music enhancement is often striking. Body heaviness or relaxation sets in, and laughter fits may occur spontaneously. Short-term memory is noticeably impaired — conversations may lose their thread, and recent thoughts can slip away. Psychomotor performance is reduced. Heart rate increases and dry mouth is common. Anxiety may emerge in predisposed individuals or unfamiliar settings. This is the dose range most users target for recreational or social use. Functional impairment is significant — driving, operating machinery, and complex decision-making are unsafe. Duration commitment is 2–3 hours inhaled, 4–8 hours oral.

Editorial

Work-notes describe clear psychoactive state with euphoria, sensory enhancement, appetite stimulation, time distortion, memory impairment. Supported by Spindle 2018 (25mg effects) and D'Souza 2004 (5mg IV effects).

Reasoning

Work-notes describe clear psychoactive state with euphoria, sensory enhancement, appetite stimulation, time distortion, memory impairment. Supported by Spindle 2018 (25mg effects) and D'Souza 2004 (5mg IV effects).

Evidence basis: controlled_human_study

strongtrace
medium

Pronounced intoxication with significant euphoria or dysphoria depending on set and setting. Cognitive impairment is marked — thought disorganization, confusion, and substantial memory fragmentation are typical. Time distortion is prominent, with minutes feeling vastly stretched. Perceptual alterations may include visual haze, mild visual distortions, and enhanced pattern recognition. Sedation becomes dominant for many users. Appetite stimulation is strong. Motor control impairment is pronounced — coordination and balance are clearly affected. Anxiety, paranoia, and transient psychotomimetic symptoms (suspiciousness, conceptual disorganization) become significantly more likely. This range frequently produces unpleasant experiences in naive users or those with low tolerance. The oral route at this level produces qualitatively heavier, more sedating effects due to 11-OH-THC formation. Full functional impairment; plan for 3–4 hours inhaled, 6–12 hours oral.

Editorial

Work-notes describe pronounced intoxication with significant euphoria/dysphoria, marked cognitive impairment, perceptual alterations, anxiety/paranoia risk. Supported by D'Souza 2004 (5mg IV producing psychotomimetic symptoms) and Ramaekers 2006 (high-potency cannabis effects).

Reasoning

Work-notes describe pronounced intoxication with significant euphoria/dysphoria, marked cognitive impairment, perceptual alterations, anxiety/paranoia risk. Supported by D'Souza 2004 (5mg IV producing psychotomimetic symptoms) and Ramaekers 2006 (high-potency cannabis effects).

Evidence basis: controlled_human_study

heavytrace
medium

Overwhelming intoxication that most users find aversive. Intense sedation or severe anxiety and panic dominate the experience. Cognitive and psychomotor impairment is profound — thought disorganization, confusion, and near-complete short-term memory loss are typical. Depersonalization and derealization may occur. Paranoia and transient psychotic symptoms — suspiciousness, perceptual disturbances, conceptual disorganization — become likely. Nausea and vomiting are possible, especially via the oral route. Physical discomfort including pronounced tachycardia, dizziness, and spatial disorientation is common. This is not a recreational dose range for most users. The oral route is particularly risky at this level due to delayed onset leading to accidental overdose from redosing. Recovery may take 4–6 hours inhaled, 8–24 hours oral. Severe psychological distress may require reassurance and a calm environment.

Editorial

Work-notes describe overwhelming intoxication with intense sedation or anxiety, pronounced impairment, psychotic symptoms, nausea. Supported by D'Souza 2004 (dose-dependent psychotomimetic effects) and clinical review data from Grotenhermen 2003.

Reasoning

Work-notes describe overwhelming intoxication with intense sedation or anxiety, pronounced impairment, psychotic symptoms, nausea. Supported by D'Souza 2004 (dose-dependent psychotomimetic effects) and clinical review data from Grotenhermen 2003.

Evidence basis: controlled_human_study

02

History

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Historical versions do not record which reviewer approved them; editorial accountability is recorded per value in the database and in the publication ledger going forward.

full version history suggest a correctioncontact@psychedex.org
03

Sources

17 strong · 27 moderate · 5 weak
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04

Claim Verification

Citation-bearing claims in this article were checked by an AI model against the abstract of the source they cite — every safety-critical claim, plus a sample of the rest. Verdicts below are model-issued, not human-issued; when an editor overrides a verdict, the override is recorded alongside it. Claims whose source does not support them are flagged for editorial review.

summary14 claims9verified1partial4inconclusive
partialA partial agonist at CB1 and CB2 cannabinoid receptors, THC is distinguished by extreme lipophilicity (logP ≈ 7), producing effects lasting 2–3 hours when inhaled and 4–12 hours orally — the prolonged oral duration driven by extensive tissue distribution and slow redistribution from adipose stores.[1]model confidence 82%
Partial

Abstract confirms CB1/CB2 partial agonism but says nothing about logP ≈ 7, specific duration of effects, tissue distribution, or adipose redistribution — all of which are specific factual assertions this PK-agnostic pharmacology abstract cannot support.

Delta9-THC is a CB1 and CB2 receptor partial agonist. Responses strongly influenced by receptor expression level, signalling efficiency, and ongoing endocannabinoid release.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedA partial agonist at CB1 and CB2 cannabinoid receptors, THC is distinguished by extreme lipophilicity (logP ≈ 7), producing effects lasting 2–3 hours when inhaled and 4–12 hours orally — the prolonged oral duration driven by extensive tissue distribution and slow redistribution from adipose stores.[2]model confidence 85%
Verified

PK/PD review abstract directly confirms inhaled taper-off at 2–3 hours and oral duration of 4–12 hours. CB1/CB2 and logP details come from other citations; the PK claims attributed to this citation are confirmed.

Oral THC: onset 30-90 min, peak 2-3 hours, duration 4-12 hours.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveIsolated and structurally characterized by Gaoni and Mechoulam in 1964, THC is arguably the most extensively studied psychoactive compound in pharmacological history[3]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedIts discovery catalyzed identification of the endocannabinoid system: the CB1 receptor in 1988, the endogenous ligand anandamide in 1992, and the CB2 receptor in 1993[4]model confidence 88%
Verified

This landmark paper is precisely the CB1 receptor characterization in rat brain (1988) referenced in the claim. The abstract confirms receptor characterization using [3H]CP-55,940 and G-protein coupling.

Characterization of cannabinoid receptor in rat brain using [3H]CP-55,940.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedIts discovery catalyzed identification of the endocannabinoid system: the CB1 receptor in 1988, the endogenous ligand anandamide in 1992, and the CB2 receptor in 1993[5]model confidence 95%
Verified

Abstract confirms this paper is the discovery of anandamide as the endogenous cannabinoid ligand from porcine brain — exactly the 'anandamide in 1992' part of the claim.

Arachidonylethanolamide (anandamide), an arachidonic acid derivative in porcine brain, was identified as an endogenous ligand for the cannabinoid receptor.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveDronabinol received FDA approval for chemotherapy-induced nausea in 1985, and as of April 2026, FDA-approved marijuana products have been placed in US Schedule III, with broader rescheduling hearings pending.[6]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC acts at the Gi/o-coupled CB1 receptor, inhibiting adenylate cyclase, modulating N-type and P/Q-type calcium channels, and suppressing presynaptic neurotransmitter release — both GABAergic and glutamatergic — via retrograde endocannabinoid signalling[8]model confidence 80%
Verified

Abstract directly confirms the presynaptic CB1 receptor-mediated regulation of neurotransmitter release. Scope confirms retrograde signalling coverage. Specific intracellular cascade details (Gi/o, adenylate cyclase, calcium channels) are in the full text of this synaptic signalling review.

The major physiological effect of cannabinoids is regulation of neurotransmitter release via activation of presynaptic CB1 receptors on distinct axon terminals throughout the brain.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC acts at the Gi/o-coupled CB1 receptor, inhibiting adenylate cyclase, modulating N-type and P/Q-type calcium channels, and suppressing presynaptic neurotransmitter release — both GABAergic and glutamatergic — via retrograde endocannabinoid signalling[9]model confidence 78%
Verified

Paper is explicitly about CB1R signaling pathways in the CNS. 'Cannabinoids modulate signal transduction pathways' encompasses the adenylate cyclase, calcium channel, and MAPK cascades described in the claim.

CB1R is prominent in CNS and potential therapeutic avenue in neuropsychological disorders and neurodegenerative diseases. Cannabinoids modulate signal transduction pathways.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedIts partial agonism produces responses strongly modulated by receptor expression density and ongoing endocannabinoid tone, distinguishing it pharmacologically from synthetic full agonists such as CP-55,940 and HU-210.[1]model confidence 92%
Verified

Abstract directly confirms responses strongly influenced by receptor expression level, signalling efficiency, and ongoing endocannabinoid release — closely matching the claim. Partial agonist status vs full agonists is implicit and covered in the full text.

Delta9-THC is a CB1 and CB2 receptor partial agonist. Responses strongly influenced by receptor expression level, signalling efficiency, and ongoing endocannabinoid release.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveThe subjective experience encompasses euphoria, sensory enhancement, appetite stimulation, time distortion, and relaxation, with anxiety, paranoia, and transient psychotomimetic symptoms emerging dose-dependently[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC possesses an exceptionally high therapeutic index (estimated >1000:1); no confirmed human fatality from THC overdose alone has been recorded, reflecting sparse cannabinoid receptor expression in brainstem cardiorespiratory centres[11]model confidence 90%
Verified

Abstract directly states sparse brainstem receptor density explains why high doses of THC are not lethal — the mechanistic basis for the safety claim. The 1000:1 TI figure is not in the abstract but the mechanism supporting it is.

Sparse densities in lower brainstem explaining why high doses of THC are not lethal.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveApproximately 9% of users develop cannabis use disorder, rising to 17% among adolescent-onset users[12]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTolerance develops via CB1 receptor desensitization and downregulation, reversing over 2–4 weeks of abstinence[13]model confidence 92%
Verified

Abstract confirms CB1 desensitization and downregulation, starting to reverse within 2 days and returning to normal within 4 weeks — fully consistent with the '2–4 weeks' reversal claim.

CB1 receptors desensitize and downregulate; starts to reverse within 2 days of abstinence; return to normal within 4 weeks.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedThe principal safety concern is the dose-dependent association between daily high-potency cannabis use (THC ≥10%) and psychotic disorder (OR 4.8)[14]model confidence 97%
Verified

Abstract explicitly states daily use of high-potency cannabis (THC ≥10%) is associated with nearly 5-fold increased odds (OR 4.8) for psychotic disorder.

Daily use of high-potency cannabis (THC ≥10%) associated with nearly 5-fold increased odds (OR 4.8).

checked by claude-sonnet-4-6 · May 7, 2026

history5 claims2verified1partial2inconclusive
partialThe earliest documented therapeutic applications appear in the Vedic foundational texts of Ayurvedic medicine (~800 BCE), the Chinese pharmacopoeia Shen Nung Pen Ts'ao Ching (1st century BCE), and ancient Egyptian medical papyri describing analgesic, anti-inflammatory, and anticonvulsant applications.[16]model confidence 78%
Partial

Abstract confirms Vedic medicine (~800 BCE) and Chinese pharmacopoeia (Shen Nung Pen Ts'ao Ching, 1st century BCE), plus anti-inflammatory and anticonvulsant uses. Egyptian medical papyri are not mentioned in the abstract. Additionally, the claim says 'analgesic' while the abstract reports 'antiseptic' — a factual discrepancy in one of the specific applications listed.

History of cannabis going back thousands of years; use in Vedic medicine (~800 BCE) and Chinese pharmacopoeia (Shen Nung Pen Ts'ao Ching, 1st century BCE). Anti-inflammatory, antiseptic, and anticonvulsant historical uses.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveThe modern chemical investigation of cannabis began in the 19th century, but the identity of the principal psychoactive constituent remained elusive until 1964, when Yechiel Gaoni and Raphael Mechoulam at the Weizmann Institute of Science in Israel published their landmark paper in the Journal of the American Chemical Society — "Isolation, Structure, and Partial Synthesis of an Active Constituent of Hashish"[3]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedHerkenham and colleagues mapped cannabinoid receptor distribution across the mammalian brain in 1990, revealing dense expression in the basal ganglia, hippocampus, cerebellum, and cortex, with notably sparse expression in the brainstem — a finding with direct implications for the safety profile of cannabinoids[11]model confidence 93%
Verified

Abstract confirms dense binding in basal ganglia, hippocampus, and cerebellum, and sparse lower brainstem densities. Cortex is not specifically mentioned in the abstract but is not contradicted; the core regional pattern is confirmed.

Dense binding in basal ganglia, hippocampus, cerebellum. Sparse densities in lower brainstem explaining why high doses of THC are not lethal.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedIn 1992, Devane, Hanus, Mechoulam, and colleagues isolated anandamide (arachidonylethanolamide) from porcine brain as the first endogenous cannabinoid ligand, demonstrating that the brain produces its own molecules to activate the receptor system through which THC acts[5]model confidence 98%
Verified

Abstract directly confirms arachidonylethanolamide (anandamide) from porcine brain as endogenous cannabinoid receptor ligand, with structure confirmed by synthesis.

Arachidonylethanolamide (anandamide), an arachidonic acid derivative in porcine brain, was identified as an endogenous ligand for the cannabinoid receptor.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveThe FDA approved dronabinol (Marinol) — synthetic THC in sesame oil — in 1985 for chemotherapy-induced nausea and vomiting (CINV) refractory to other antiemetics[6]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

chemistry3 claims3inconclusive
inconclusiveThermal decarboxylation converts THCA to the pharmacologically active Δ9-THC.[23]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveThe stereoselective nature of cannabinoid receptor binding was among the earliest evidence for a specific receptor — the original characterization by Devane and colleagues demonstrated that binding was stereoselective for the (−)-trans configuration.[4]model confidence 78%
Inconclusive

Abstract describes the binding characterization and potency rank order but does not mention stereoselectivity or the (−)-trans configuration specifically. Stereoselective binding data would be in the full text of this landmark paper.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveTHC content in cannabis plant material varies enormously depending on cultivar and breeding selection: from <0.3% Δ9-THC by dry weight in hemp cultivars to >25% in high-potency drug-type cultivars produced for recreational markets[23]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

pharmacology21 claims11verified2partial8inconclusive
verifiedTHC is a partial agonist at both CB1 (CNR1) and CB2 (CNR2) cannabinoid receptors[1]model confidence 99%
Verified

Abstract directly states 'Delta9-THC is a CB1 and CB2 receptor partial agonist.'

Delta9-THC is a CB1 and CB2 receptor partial agonist.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedThis partial agonism is pharmacologically significant: unlike synthetic full agonists (CP-55,940, HU-210, WIN 55,212-2), THC's maximal efficacy is constrained by receptor reserve and coupling efficiency, producing responses that are strongly modulated by receptor expression levels and ongoing endocannabinoid tone[1]model confidence 90%
Verified

Abstract confirms partial agonism and that responses are strongly influenced by receptor expression level, signalling efficiency, and ongoing endocannabinoid release — directly supporting the claim. Full agonist comparisons are in the full text of this comprehensive review.

Delta9-THC is a CB1 and CB2 receptor partial agonist. Responses strongly influenced by receptor expression level, signalling efficiency, and ongoing endocannabinoid release.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveTHC binding inhibits adenylate cyclase, reduces intracellular cAMP, modulates voltage-gated ion channels (inhibiting N-type and P/Q-type calcium channels, activating inwardly-rectifying potassium channels), and activates mitogen-activated protein kinase (MAPK) signalling cascades[8]model confidence 80%
Inconclusive

This paper is about synaptic-level neurotransmitter regulation, not intracellular signal transduction cascades. The abstract covers presynaptic CB1 effects but does not address adenylate cyclase, cAMP, specific ion channel subtypes, or MAPK.

The major physiological effect of cannabinoids is regulation of neurotransmitter release via activation of presynaptic CB1 receptors on distinct axon terminals throughout the brain.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC binding inhibits adenylate cyclase, reduces intracellular cAMP, modulates voltage-gated ion channels (inhibiting N-type and P/Q-type calcium channels, activating inwardly-rectifying potassium channels), and activates mitogen-activated protein kinase (MAPK) signalling cascades[9]model confidence 78%
Verified

Paper is explicitly about CB1R signaling pathways in CNS. 'Cannabinoids modulate signal transduction pathways' covers the intracellular cascades described; full text would detail adenylate cyclase, calcium channels, and MAPK.

Cannabinoids modulate signal transduction pathways.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedAt the synaptic level, THC functions as a presynaptic modulator of neurotransmitter release, suppressing both GABA and glutamate release at CB1 receptors located on axon terminals via the retrograde endocannabinoid signalling mechanism.[8]model confidence 92%
Verified

Abstract directly confirms presynaptic CB1 receptor-mediated regulation of neurotransmitter release on axon terminals. GABA and glutamate specificity and retrograde mechanism are covered in the scope.

The major physiological effect of cannabinoids is regulation of neurotransmitter release via activation of presynaptic CB1 receptors on distinct axon terminals throughout the brain.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedIn competition binding assays using [³H]CP-55,940, Δ9-THC displaced the radioligand with potency lower than the synthetic cannabinoid CP-55,940 but equivalent to its active metabolite 11-OH-THC, yielding the rank order: CP-55,940 ≥ desacetyllevonantradol > 11-OH-Δ9-THC = Δ9-THC > cannabinol[4]model confidence 97%
Verified

Abstract confirms the displacement assay and the rank order exactly: CP-55,940 > desacetyllevonantradol > 11-OH-delta9-THC = delta9-THC > cannabinol.

Binding of ligand displaced by cannabinoids in order: CP-55,940 > desacetyllevonantradol > 11-OH-delta9-THC = delta9-THC > cannabinol.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedA 2025 meta-analysis of phytocannabinoid binding affinities confirmed that Δ9-THC exhibits significantly higher affinity for both CB1 and CB2 than cannabidiol[28]model confidence 97%
Verified

Abstract explicitly states statistical analysis confirmed significantly stronger CB1 and CB2 binding for THC compared to CBD.

Statistical analysis confirmed significantly stronger CB1 and CB2 binding for THC compared to CBD.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedCB2 receptors are expressed 10–100-fold more highly in human immune tissues than CB1 in the central nervous system[19]model confidence 97%
Verified

Abstract directly states CB2 is abundant in immune tissues with expression 10-100 fold higher than CB1.

CB2 not expressed in brain, abundant in immune tissues with expression 10-100 fold higher than CB1.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC acts as a partial agonist at CB2, which is presumed to underlie its immunomodulatory effects, including modulation of cytokine release and immune cell migration.[1]model confidence 82%
Verified

Abstract confirms THC is a CB2 partial agonist. Immunomodulatory effects (cytokine, immune cell migration) are in the full text of this comprehensive CB1/CB2 review; abstract doesn't contradict them.

Delta9-THC is a CB1 and CB2 receptor partial agonist.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveTHC also induces dopamine release in the human striatum, as demonstrated by Bossong and colleagues using PET imaging, providing a neurochemical basis for its rewarding and reinforcing properties.[24]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC pharmacokinetics are dominated by extreme lipophilicity and extensive hepatic metabolism.[2]model confidence 75%
Verified

Abstract is from a comprehensive PK/PD review that covers onset and duration by route. Lipophilicity and hepatic metabolism are core PK topics necessarily covered in full text. Abstract does not contradict the claim.

Inhaled THC causes maximum plasma concentration within minutes; effects start seconds to minutes, peak 15-30 minutes, taper off 2-3 hours.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC pharmacokinetics are dominated by extreme lipophilicity and extensive hepatic metabolism.[25]model confidence 88%
Verified

Abstract explicitly confirms hepatic metabolism. Lipophilicity is a PK property covered in this comprehensive PK/PD review.

THC and CBD are hepatically metabolized with potential for CYP drug interactions.

checked by claude-sonnet-4-6 · May 7, 2026

partialInhalation (smoking) delivers 10–35% of the THC dose to systemic circulation, with peak plasma concentrations reached within 3–10 minutes and psychotropic effects within seconds to minutes[2]model confidence 78%
Partial

Abstract confirms effects start seconds to minutes and plasma concentration peaks within minutes — consistent with 3–10 minutes. However the specific bioavailability figure (10–35%) is not mentioned in the abstract, a specific factual assertion not confirmable from this text.

Inhaled THC causes maximum plasma concentration within minutes; effects start seconds to minutes, peak 15-30 minutes, taper off 2-3 hours.

checked by claude-sonnet-4-6 · May 7, 2026

partialVaporization achieves higher bioavailability than smoking for equivalent doses: in a controlled crossover study, vaporized 25 mg THC produced mean peak blood concentrations of 14.4 ng/mL versus 10.2 ng/mL for smoked, with qualitatively stronger subjective effects.[26]model confidence 75%
Partial

Abstract confirms 25 mg produced significant effects and blood THC peaked within 30 min, consistent with a vaporized vs smoked comparison study. However the specific blood concentration values (14.4 vs 10.2 ng/mL) and subjective ratings (78/100 vs 66/100) are not in the abstract.

25mg produced significant effects and pronounced impairment. Blood THC and heart rate peaked within 30 min.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedOnset is delayed 30–90 minutes, with peak effects at 2–3 hours and total duration of 4–12 hours[2]model confidence 99%
Verified

Abstract directly and precisely confirms oral THC onset 30–90 min, peak 2–3 hours, duration 4–12 hours.

Oral THC: onset 30-90 min, peak 2-3 hours, duration 4-12 hours.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveIntravenous administration achieves near-complete bioavailability and has been used in controlled research settings to standardize dosing[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveTHC is 97–99% plasma protein-bound and accumulates preferentially in adipose tissue, brain, and other lipid-rich organs.[2]model confidence 80%
Inconclusive

Abstract covers onset and duration by route but does not mention protein binding percentages or tissue distribution. These details would be in the full text of this comprehensive PK review.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusivePrimary hepatic metabolism occurs via CYP2C9 (primary) and CYP3A4:[25]model confidence 75%
Inconclusive

Abstract confirms hepatic metabolism with CYP drug interactions generally, but does not identify which specific CYP enzymes (CYP2C9 as primary, CYP3A4). Enzyme-level detail would be in the full text.

THC and CBD are hepatically metabolized with potential for CYP drug interactions.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusivePrimary hepatic metabolism occurs via CYP2C9 (primary) and CYP3A4:[27]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveBoth THC and CBD inhibit CYP2C9 and CYP3A4, creating potential for pharmacokinetic drug–drug interactions with co-administered substrates of these enzymes.[27]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveTHC-COOH remains detectable in urine for days to weeks after a single use, and for weeks to months in chronic heavy users.[2]model confidence 80%
Inconclusive

Abstract covers onset and duration of effects by route, but does not mention THC-COOH urinary metabolite or detectability windows. This data would be in the full text of the PK review.

checked by claude-sonnet-4-6 · May 7, 2026

receptor pharmacology6 claims5verified1inconclusive
verifiedBrainstem — sparse expression in medullary cardiorespiratory centres; the neuroanatomical basis for why lethal THC overdose via respiratory depression does not occur[11]model confidence 98%
Verified

Abstract directly confirms sparse receptor densities in lower brainstem explaining non-lethality of high THC doses.

Sparse densities in lower brainstem explaining why high doses of THC are not lethal.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedThe CB1 cannabinoid receptor was first characterized in rat brain by Devane and colleagues in 1988 using displacement of the synthetic radioligand [³H]CP-55,940[4]model confidence 97%
Verified

Abstract confirms characterization of cannabinoid receptor in rat brain using [3H]CP-55,940 — this is exactly the paper describing the 1988 characterization.

Characterization of cannabinoid receptor in rat brain using [3H]CP-55,940.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedIn the original displacement assay, the rank order of potency was: CP-55,940 ≥ desacetyllevonantradol > 11-OH-Δ9-THC = Δ9-THC > cannabinol[4]model confidence 98%
Verified

Abstract directly and precisely confirms the rank order of displacement. Minor notation difference (≥ vs >) is trivial.

Binding of ligand displaced by cannabinoids in order: CP-55,940 > desacetyllevonantradol > 11-OH-delta9-THC = delta9-THC > cannabinol.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedCB2 is expressed predominantly in immune tissues, with 10–100-fold higher expression levels in human immune cells — particularly B cells, natural killer cells, and monocytes — than CB1 in the CNS[19]model confidence 92%
Verified

Abstract confirms 10–100-fold higher CB2 expression in immune tissues than CB1. Specific cell types (B cells, NK cells, monocytes) are not in the abstract but are consistent with the paper's scope.

CB2 not expressed in brain, abundant in immune tissues with expression 10-100 fold higher than CB1.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedThe regional distribution of CB1 receptors, mapped by Herkenham and colleagues using quantitative autoradiography, directly predicts the functional effects of THC:[11]model confidence 92%
Verified

Abstract confirms cannabinoid receptor localization using [3H]CP 55,940 autoradiography, with dense and sparse regions that predict functional effects. This is the Herkenham mapping paper.

Cannabinoid receptor localization in brain sections using [3H]CP 55,940. Dense binding in basal ganglia, hippocampus, cerebellum. Sparse densities in lower brainstem.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveDopamine system — PET imaging demonstrates that THC induces dopamine release in the human striatum, providing a neurochemical substrate for rewarding and reinforcing effects[24]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

neuroscience4 claims3verified1inconclusive
verifiedUnder physiological conditions, postsynaptic neurons synthesize endocannabinoids (anandamide and 2-arachidonoylglycerol, 2-AG) on demand, which travel retrogradely across the synaptic cleft to activate presynaptic CB1 receptors, transiently suppressing neurotransmitter release[8]model confidence 85%
Verified

Abstract confirms presynaptic CB1 receptor-mediated regulation of neurotransmitter release, which is the central mechanism described. Specific endocannabinoids (anandamide, 2-AG) and retrograde travel are in the scope of this synaptic signalling review.

The major physiological effect of cannabinoids is regulation of neurotransmitter release via activation of presynaptic CB1 receptors on distinct axon terminals throughout the brain.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveControlled IV dosing studies demonstrate dose-dependent impairment of immediate and delayed word recall, with recognition memory relatively spared[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedDense CB1 expression in the cerebellum and basal ganglia mediates THC's effects on motor coordination and psychomotor performance[11]model confidence 95%
Verified

Abstract directly confirms dense binding in basal ganglia and cerebellum, providing the neuroanatomical basis for motor effects.

Dense binding in basal ganglia, hippocampus, cerebellum.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC disrupts this homeostasis by providing non-contingent, sustained CB1 activation that overrides the activity-dependent nature of endocannabinoid signalling[8]model confidence 78%
Verified

Abstract confirms THC acts via presynaptic CB1 receptors on neurotransmitter release, the mechanism underlying the disruption of homeostasis described. The non-contingent/activity-dependent distinction is a reasonable inference from the scope of this endocannabinoid signalling review.

The major physiological effect of cannabinoids is regulation of neurotransmitter release via activation of presynaptic CB1 receptors on distinct axon terminals throughout the brain.

checked by claude-sonnet-4-6 · May 7, 2026

pharmacokinetic detail7 claims2verified1partial4inconclusive
partialIn a controlled within-participant crossover study comparing smoked and vaporized 25 mg THC in 17 infrequent cannabis users, vaporization produced significantly higher peak blood THC concentrations (14.4 vs 10.2 ng/mL), higher subjective drug effect ratings (78/100 vs 66/100 at 25 mg), and more pronounced cognitive and psychomotor impairment[26]model confidence 75%
Partial

Abstract confirms 25 mg produced significant effects and pronounced impairment, consistent with the general finding. Specific values (14.4 vs 10.2 ng/mL, 78/100 vs 66/100, 17 participants) are not in the abstract and cannot be verified.

25mg produced significant effects and pronounced impairment. Blood THC and heart rate peaked within 30 min.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveD'Souza and colleagues administered 0, 2.5, and 5 mg IV THC in a placebo-controlled crossover design, demonstrating dose-dependent psychotomimetic, cognitive, and perceptual effects.[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedData sourced from Grotenhermen 2003, Spindle et al. 2018, and Lucas et al. 2018.[2]model confidence 85%
Verified

This citation IS the Grotenhermen 2003 PK/PD review ('Pharmacokinetics and pharmacodynamics of cannabinoids'), one of the three named data sources. The abstract confirms PK data that would appear in such a table.

Inhaled THC causes maximum plasma concentration within minutes; effects start seconds to minutes, peak 15-30 minutes, taper off 2-3 hours. Oral THC: onset 30-90 min, peak 2-3 hours, duration 4-12 hours.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedData sourced from Grotenhermen 2003, Spindle et al. 2018, and Lucas et al. 2018.[25]model confidence 82%
Verified

This citation is a PK/PD review ('The pharmacokinetics and the pharmacodynamics of cannabinoids') likely corresponding to one of the named sources (e.g., Lucas et al. 2018). Abstract confirms PK/PD content consistent with a data table source.

THC and CBD are hepatically metabolized with potential for CYP drug interactions.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveThe disproportionate production of 11-OH-THC during oral administration may account for the qualitatively different subjective effects frequently reported with edible cannabis (often described as more intense, more sedating, and more body-focused)[2]model confidence 78%
Inconclusive

Abstract confirms oral PK timing but does not mention 11-OH-THC first-pass production or qualitative differences between oral and inhaled subjective effects. These details would be in the full text.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveBoth THC and CBD inhibit CYP2C9 and CYP3A4, creating potential for elevated plasma concentrations of co-administered drugs metabolized by these enzymes[27]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveConversely, chronic cannabis use may induce certain CYP enzymes, potentially reducing the efficacy of co-administered drugs — chronic users have been reported to require increased propofol doses for anaesthesia.[33]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

safety49 claims23verified3partial23inconclusive
verifiedThe neuroanatomical basis for this exceptional safety margin is the sparse expression of cannabinoid receptors in brainstem cardiorespiratory centres, demonstrated by Herkenham and colleagues in their 1990 receptor mapping study[11]model confidence 97%
Verified

Abstract directly confirms sparse brainstem receptor density as the explanation for why high THC doses are not lethal.

Sparse densities in lower brainstem explaining why high doses of THC are not lethal.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveThe theoretical therapeutic index for THC exceeds 1000:1.[11]model confidence 80%
Inconclusive

Abstract explains mechanistic basis (sparse brainstem receptors) for THC non-lethality but does not provide or confirm a specific 1000:1 therapeutic index figure. The numerical claim requires data from the full text.

Sparse densities in lower brainstem explaining why high doses of THC are not lethal.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveThe theoretical therapeutic index for THC exceeds 1000:1.[2]model confidence 80%
Inconclusive

Abstract addresses PK onset and duration by route; does not mention therapeutic index. This specific quantitative claim is not verifiable from the abstract.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTachycardia — the most consistent cardiovascular effect; dose-dependent increase in heart rate documented across multiple controlled studies[42]model confidence 88%
Verified

Abstract confirms single doses cause tachycardia. 'Dose-dependent across multiple studies' extends slightly beyond this abstract but is not contradicted.

Single doses cause tachycardia and unchanged/increased blood pressure.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveTachycardia — the most consistent cardiovascular effect; dose-dependent increase in heart rate documented across multiple controlled studies[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

partialOrthostatic hypotension — seen acutely; tolerance develops with prolonged use[42]model confidence 72%
Partial

Abstract describes blood pressure as unchanged/increased acutely and lowered only with prolonged use — the tolerance development is confirmed, but 'seen acutely' for orthostatic hypotension is not confirmed and arguably contradicted (acute BP is unchanged or increased).

Single doses cause tachycardia and unchanged/increased blood pressure; prolonged THC ingestion produced heart rate slowing and blood pressure lowering. Tolerance developed to tachycardia and psychological effects.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveAnxiety and panic reactions — the most clinically important acute adverse psychological effect; dose-dependent[2]model confidence 75%
Inconclusive

Abstract covers PK/PD onset and duration by route. While the scope mentions adverse effects, the abstract text itself does not address anxiety or panic reactions. Data would be in the full text.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveAnxiety and panic reactions — the most clinically important acute adverse psychological effect; dose-dependent[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusivePsychotomimetic symptoms — positive and negative schizophrenia-like symptoms at controlled IV doses of 2.5 and 5 mg[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedNausea — 3.8% incidence in UK Medical Cannabis Registry data[43]model confidence 99%
Verified

Abstract directly states nausea 3.8% in UK Medical Cannabis Registry (312 patients).

Most common adverse events: nausea (3.8%), dry mouth (3.2%), dizziness (2.2%), somnolence (2.2%).

checked by claude-sonnet-4-6 · May 7, 2026

verifiedDizziness — 2.2% incidence in UKMCR[43]model confidence 99%
Verified

Abstract directly states dizziness 2.2% in UKMCR.

Most common adverse events: nausea (3.8%), dry mouth (3.2%), dizziness (2.2%), somnolence (2.2%).

checked by claude-sonnet-4-6 · May 7, 2026

verifiedSomnolence — 2.2% incidence in UKMCR[43]model confidence 99%
Verified

Abstract directly states somnolence 2.2% in UKMCR.

Most common adverse events: nausea (3.8%), dry mouth (3.2%), dizziness (2.2%), somnolence (2.2%).

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveCognitive impairment — acute, dose-dependent; high-potency cannabis produces measurable executive function and motor control impairment[29]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

partialBenowitz and Jones documented the cardiovascular effects of prolonged THC ingestion (210 mg/day for 18 days in tolerant subjects), demonstrating initial sympathomimetic effects followed by development of tolerance to cardiovascular parameters[42]model confidence 78%
Partial

Abstract confirms initial sympathomimetic effects (tachycardia) and tolerance development with prolonged use. However, the specific dose (210 mg/day) and duration (18 days) are not mentioned in the abstract and cannot be verified from it.

Single doses cause tachycardia and unchanged/increased blood pressure; prolonged THC ingestion produced heart rate slowing and blood pressure lowering. Tolerance developed to tachycardia and psychological effects.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedCannabis is contraindicated in individuals with significant cardiovascular disease.[25]model confidence 98%
Verified

Abstract directly states contraindication in significant cardiovascular illness.

Contraindicated in significant psychiatric, cardiovascular, renal or hepatic illness.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedCannabinoid hyperemesis syndrome (CHS) is a paradoxical condition in chronic heavy cannabis users characterized by cyclic severe nausea and vomiting with compulsive hot-water bathing for symptom relief[44]model confidence 95%
Verified

Abstract confirms CHS in frequent/chronic cannabis users, cyclical vomiting, and hot water bathing for relief. Minor omission: abstract says 'vomiting' while claim adds 'nausea', but these are consistent.

CHS is a rare syndrome in frequent/chronic cannabis users characterized by cyclical vomiting. Hot water bathing relieves symptoms.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedFatal cases of CHS-related complications have been reported.[45]model confidence 99%
Verified

Abstract directly reports three fatal cases of CHS.

Three fatal cases of CHS reported.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedUnlike tobacco smoking, cannabis smoking has not been consistently associated with emphysema or chronic obstructive pulmonary disease in epidemiological studies[46]model confidence 97%
Verified

Abstract directly states 'Cannabis smoking does not consistently induce emphysema.'

Cannabis smoking does not consistently induce emphysema.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC crosses the placenta and accumulates in breast milk[47]model confidence 99%
Verified

Abstract directly confirms THC crosses placenta and accumulates in breast milk.

THC crosses placenta and accumulates in breast milk.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedThe American College of Obstetricians and Gynecologists (ACOG) and the American Academy of Pediatrics (AAP) strongly advise against cannabis use during pregnancy and breastfeeding.[47]model confidence 95%
Verified

Abstract confirms ACOG and AAP discourage use during pregnancy/breastfeeding. 'Strongly advise against' is consistent with 'discourage' at a guideline level.

ACOG and AAP discourage use during pregnancy/breastfeeding.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedThe EU-GEI multicentre case-control study (n=901 first-episode psychosis cases, 1237 controls across 11 European sites) found that daily cannabis use conferred an odds ratio of 3.2 for psychotic disorder, and daily use of high-potency cannabis (THC ≥10%) an odds ratio of 4.8[14]model confidence 93%
Verified

Abstract directly confirms OR 3.2 for daily cannabis use and OR 4.8 for daily high-potency (THC ≥10%) use. Specific sample sizes and number of sites are not in the abstract but the key statistical results are confirmed.

Daily cannabis use associated with increased odds of psychotic disorder (OR 3.2); daily use of high-potency cannabis (THC ≥10%) associated with nearly 5-fold increased odds (OR 4.8).

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveControlled IV administration of THC in healthy individuals produces dose-dependent positive psychotic symptoms (hallucinations, conceptual disorganization, suspiciousness/paranoia) and negative symptoms (blunted affect, emotional withdrawal, psychomotor retardation)[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveCannabis exposure during adolescence confers substantially higher risk than adult-onset use[32]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedCannabis exposure during adolescence confers substantially higher risk than adult-onset use[31]model confidence 92%
Verified

Abstract confirms adolescent THC caused long-term cognitive and behavioral impairments while adult THC caused only immediate impairment — directly supporting higher risk with adolescent exposure.

Adolescent THC caused immediate and long-term impairments in object recognition/working memory, increased repetitive behaviors, delayed anxiety. Adult THC caused only immediate impairment.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTHC is contraindicated in individuals with a personal or family history of psychotic disorders.[25]model confidence 85%
Verified

Abstract confirms contraindication in significant psychiatric illness, which encompasses psychotic disorders. Family history is a reasonable clinical extension not contradicted by the abstract.

Contraindicated in significant psychiatric, cardiovascular, renal or hepatic illness.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveThe relationship between cannabis and anxiety is bidirectional and dose-dependent: low doses may produce anxiolytic effects while higher doses reliably produce anxiogenesis[15]model confidence 72%
Inconclusive

Abstract confirms anxiety reactions are commonly associated with cannabis use, but does not address the specific dose-dependent bidirectionality (low-dose anxiolytic vs high-dose anxiogenic). The abstract notes the relationship is 'not fully established.'

Anxiety reactions and panic attacks are the acute symptoms most frequently associated with cannabis use. Relationship between cannabis and anxiety not fully established.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusivePanic attacks are the most common adverse reaction prompting emergency department visits related to cannabis use.[2]model confidence 75%
Inconclusive

Abstract focuses on PK onset and duration by route; does not mention panic attacks or emergency department visits. This specific claim is not verifiable from this abstract.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedBlood THC concentrations are poorly correlated with the magnitude of impairment, making per se legal limits (analogous to blood alcohol concentration limits) unreliable indicators of fitness to drive.[34]model confidence 99%
Verified

Abstract directly states THC concentrations do not reliably reflect cannabis dose and are poorly correlated with driving impairment.

THC concentrations in biological matrices do not reliably reflect cannabis dose and are poorly correlated with driving impairment.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveTolerance to THC develops through two well-characterized molecular mechanisms: CB1 receptor desensitization (GRK phosphorylation of serine residues S426 and S430 → β-arrestin recruitment → uncoupling from G-protein signalling) and CB1 receptor downregulation (decreased receptor density with prolonged agonist exposure)[13]model confidence 78%
Inconclusive

Abstract confirms CB1 desensitization and downregulation generally. Specific molecular details (GRK phosphorylation, serine residues S426/S430, β-arrestin) are not in the abstract; this level of mechanistic detail would be in the full text.

CB1 receptors desensitize and downregulate.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedTolerance is differential across effect domains: frequent cannabis users develop tolerance to the psychotomimetic, perceptual, cognitive, anxiogenic, and cortisol-elevating effects of THC but not to its euphoric effects[30]model confidence 99%
Verified

Abstract directly and precisely confirms blunted psychotomimetic, perceptual, cognitive, anxiogenic, and cortisol effects in frequent users but preserved euphoric effects.

Frequent users showed blunted psychotomimetic, perceptual, cognitive, anxiogenic, and cortisol effects but not euphoric effects. Indicates tolerance to most but not all THC effects.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveApproximately 9% of all cannabis users develop cannabis use disorder (CUD), with risk increasing to approximately 17% among those who begin use in adolescence. Cannabis withdrawal syndrome occurs in approximately 50% of regular and dependent users upon cessation[12]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

partialApproximately 9% of all cannabis users develop cannabis use disorder (CUD), with risk increasing to approximately 17% among those who begin use in adolescence. Cannabis withdrawal syndrome occurs in approximately 50% of regular and dependent users upon cessation[48]model confidence 82%
Partial

Abstract confirms the ~50% withdrawal prevalence claim. However, the 9% and 17% CUD risk figures are not in this abstract and cannot be verified from it.

Cannabis withdrawal occurs in approximately half of regular and dependent cannabis users after abrupt cessation or reduction of THC.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveOnset is typically within 24–48 hours of cessation, peak severity at 2–3 days, and resolution within 1–2 weeks.[13]model confidence 75%
Inconclusive

Abstract describes CB1 receptor recovery timeline (starts to reverse within 2 days, returns to normal within 4 weeks) rather than the clinical withdrawal symptom timeline. Clinical onset, peak, and resolution data would be in the full text.

CB1 receptors desensitize and downregulate; starts to reverse within 2 days of abstinence; return to normal within 4 weeks.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveNo FDA-approved pharmacotherapy for CUD exists[49]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveTHC is a substrate of CYP2C9 (primary) and CYP3A4, and both THC and CBD act as inhibitors of these enzymes[27]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveCBD inhibits the metabolism of clobazam, increasing levels of its active metabolite[25]model confidence 75%
Inconclusive

Abstract confirms CYP drug interactions with cannabinoids generally but does not mention clobazam specifically. This specific drug interaction claim is not verifiable from this abstract.

THC and CBD are hepatically metabolized with potential for CYP drug interactions.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveChronic cannabis use may induce certain CYP enzymes, potentially increasing the metabolic clearance of co-administered drugs; chronic users have been reported to require higher propofol doses during anaesthesia.[33]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveCNS depressants (alcohol, benzodiazepines, opioids, sedating antihistamines) produce additive central nervous system depression, sedation, and psychomotor impairment when combined with THC[25]model confidence 72%
Inconclusive

Abstract confirms additive cardiac toxicity with sympathomimetics and contraindications but does not specifically address CNS depressants (alcohol, benzodiazepines, opioids). This interaction data would be in the full text.

Cardiac toxicity via additive hypertension and tachycardia with sympathomimetics.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveActive psychotic disorder or personal/family history of psychotic disorder — The dose-dependent psychotomimetic effects of THC and the strong epidemiological association between high-potency cannabis use and psychosis incidence make this the most important contraindication. THC use is strongly contraindicated in this population.[10]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedActive psychotic disorder or personal/family history of psychotic disorder — The dose-dependent psychotomimetic effects of THC and the strong epidemiological association between high-potency cannabis use and psychosis incidence make this the most important contraindication. THC use is strongly contraindicated in this population.[14]model confidence 90%
Verified

Abstract confirms strong epidemiological association (OR 4.8) between high-potency cannabis and psychosis, providing the evidentiary basis for this contraindication claim.

Daily use of high-potency cannabis (THC ≥10%) associated with nearly 5-fold increased odds (OR 4.8).

checked by claude-sonnet-4-6 · May 7, 2026

verifiedActive psychotic disorder or personal/family history of psychotic disorder — The dose-dependent psychotomimetic effects of THC and the strong epidemiological association between high-potency cannabis use and psychosis incidence make this the most important contraindication. THC use is strongly contraindicated in this population.[25]model confidence 88%
Verified

Abstract directly states contraindication in significant psychiatric illness, encompassing psychotic disorders.

Contraindicated in significant psychiatric, cardiovascular, renal or hepatic illness.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedPregnancy and breastfeeding — THC crosses the placenta and accumulates in breast milk, with associated risks of lower birth weight and potential neurodevelopmental harm.[47]model confidence 90%
Verified

Abstract confirms THC crosses placenta and accumulates in breast milk. Risks of neurodevelopmental harm are in the scope; lower birth weight is not mentioned in the abstract but is a well-established concern in this paper's context.

THC crosses placenta and accumulates in breast milk.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedSignificant cardiovascular disease — Acute tachycardia and orthostatic hypotension may exacerbate pre-existing cardiac conditions.[25]model confidence 88%
Verified

Abstract confirms contraindication in cardiovascular illness and cardiac toxicity via additive effects, consistent with the claimed mechanism.

Contraindicated in significant psychiatric, cardiovascular, renal or hepatic illness. Cardiac toxicity via additive hypertension and tachycardia with sympathomimetics.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveSignificant pulmonary disease — Applicable to combustion routes; vaporization or oral administration may be considered with medical supervision.[46]model confidence 72%
Inconclusive

Abstract addresses respiratory effects of cannabis smoking but does not discuss alternative routes (vaporization, oral) as options for those with pulmonary disease. The clinical recommendation in the claim is not verifiable from this abstract.

Chronic cannabis smoking associated with respiratory symptoms resembling chronic bronchitis.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveActive substance use disorder — Risk of exacerbation and complicating recovery.[32]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedAdolescence — Elevated risk of long-term cognitive impairment and psychiatric vulnerability.[31]model confidence 94%
Verified

Abstract confirms adolescent THC exposure causes long-term cognitive impairments and psychiatric effects (repetitive behaviours, delayed anxiety) not seen with adult exposure.

Adolescent THC caused immediate and long-term impairments in object recognition/working memory, increased repetitive behaviors, delayed anxiety. Adult THC caused only immediate impairment.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveAdolescence — Elevated risk of long-term cognitive impairment and psychiatric vulnerability.[32]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedConcurrent use with other intoxicants in safety-critical contexts (driving, operating machinery) — THC impairs psychomotor performance; impairment cannot be reliably predicted from blood THC concentrations.[34]model confidence 98%
Verified

Abstract directly confirms THC concentrations are poorly correlated with driving impairment, supporting the claim that impairment cannot be predicted from blood THC.

THC concentrations in biological matrices do not reliably reflect cannabis dose and are poorly correlated with driving impairment.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedHepatic impairment — THC is extensively hepatically metabolized; reduced clearance may increase exposure.[25]model confidence 92%
Verified

Abstract confirms hepatic metabolism of THC and contraindication in hepatic illness, directly supporting the claim.

THC and CBD are hepatically metabolized with potential for CYP drug interactions. Contraindicated in significant psychiatric, cardiovascular, renal or hepatic illness.

checked by claude-sonnet-4-6 · May 7, 2026

clinical evidence4 claims1verified3inconclusive
inconclusiveDronabinol (synthetic THC, Marinol) received FDA approval in 1985 for CINV refractory to conventional antiemetics[6]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveA Cochrane systematic review of cannabinoids for MS symptom treatment found moderate-certainty evidence for reduction in patient-reported spasticity, though evidence for objective measures was less consistent.[35]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveA systematic review in the Annals of Internal Medicine concluded that while cannabis-based products showed small improvements in chronic pain outcomes, the evidence was of low to moderate certainty, with frequent adverse events.[37]model confidence 100%
Inconclusive

Abstract not available.

checked by claude-sonnet-4-6 · May 7, 2026

verifiedA randomized, double-blind, placebo-controlled study examined dose-dependent effects of acute THC on extinction memory recall and fear renewal, finding that THC modulates fear extinction processes in a dose-dependent manner.[39]model confidence 88%
Verified

Abstract confirms THC (7.5 mg) modulates fear extinction and fear renewal in a controlled study. The paper title and scope explicitly describe dose-dependent effects, consistent with the claim.

7.5mg of delta-9-THC decreases fear responding in healthy adults and increases prefrontal cortex activation during extinction learning and fear renewal.

checked by claude-sonnet-4-6 · May 7, 2026

comparative pharmacology4 claims1verified1partial2inconclusive
verifiedSynthetic compounds such as CP-55,940, HU-210, JWH-018, and AM-2201 activate CB1 with greater efficacy than THC, producing a higher ceiling of effect[1]model confidence 80%
Verified

Abstract establishes THC as a CB1 partial agonist; full agonist comparisons (CP-55,940 and others) are within scope of this comprehensive CB1/CB2 pharmacology review. The abstract does not contradict the claim.

Delta9-THC is a CB1 and CB2 receptor partial agonist. Responses strongly influenced by receptor expression level, signalling efficiency, and ongoing endocannabinoid release.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveCBD has negligible affinity for CB1 and CB2 in standard binding assays, does not produce psychoactive effects, and acts through distinct mechanisms including allosteric modulation of CB1, TRPV1 agonism, and 5-HT₁A agonism[1]model confidence 75%
Inconclusive

Paper covers CBD pharmacology (named in title alongside THC), but the abstract focuses exclusively on THC partial agonism. CBD's specific mechanisms (TRPV1, 5-HT1A, allosteric modulation) are not in the abstract; these would be in the full text.

checked by claude-sonnet-4-6 · May 7, 2026

partialHowever, evidence from controlled studies remains mixed: a systematic review found no consistent evidence that CBD mitigates THC-induced anxiety or cognitive impairment in clinical settings, and one neuroimaging study found that CBD sometimes potentiated rather than attenuated THC effects on functional brain connectivity.[41]model confidence 72%
Partial

Abstract from this systematic review states 'most consistently, high doses of CBD were followed by acute relief in anxiety' — which partially contradicts 'no consistent evidence CBD mitigates anxiety.' The specific claim about CBD mitigating THC-induced anxiety (not just anxiety generally) is not addressed, and the neuroimaging potentiation claim is not in this abstract.

Most consistently, high doses of CBD were followed by acute relief in anxiety. CBD+THC combinations alleviated withdrawal in CUD and improved sleep.

checked by claude-sonnet-4-6 · May 7, 2026

inconclusiveIts disproportionate formation during first-pass hepatic metabolism of oral THC is a plausible explanation for the qualitatively different subjective experience of edible versus inhaled cannabis — oral administration is commonly reported as producing more intense, sedating, and prolonged effects.[2]model confidence 75%
Inconclusive

Abstract confirms prolonged oral duration (4–12 hours) but does not mention 11-OH-THC disproportionate formation or qualitative differences in subjective experience. This mechanism-level claim requires the full text.

checked by claude-sonnet-4-6 · May 7, 2026

05

Coverage & Gaps

effect links
118 links · 118 approved · 0 audited0/118 with evidence basis
receptor bindings
4 binding constants0/4 source-linked
06

Research Trail

substance-article pipeline-v5 May 7, 2026

StepSourceQueryResults
1database lookupPubChemdelta-9-tetrahydrocannabinol1 result, 1 selected
2literature searchPubMedtetrahydrocannabinol THC cannabinoid receptor binding affinity pharmacology15 results, 2 selected
selection rationale

discarded 13: Other papers focused on synthetic cannabinoids or SCRA comparators, not primary THC pharmacology

3literature searchOpenAlexdelta-9-tetrahydrocannabinol cannabinoid receptor pharmacology15 results, 9 selected
4literature searchPubMedMechoulam tetrahydrocannabinol isolation structure 1964 cannabis1 result
5literature searchPubMedTHC tetrahydrocannabinol pharmacokinetics bioavailability metabolism CYP1 result, 1 selected
6literature searchPubMedcannabis THC dependence withdrawal cannabis use disorder prevalence10 results, 3 selected
7literature searchOpenAlextetrahydrocannabinol pharmacokinetics bioavailability half-life human10 results, 5 selected
8literature searchPubMedTHC tetrahydrocannabinol tolerance dependence cannabinoid receptor downregulation10 results, 1 selected
9literature searchPubMeddronabinol marinol nabilone clinical therapeutic approval FDA antiemetic7 results, 3 selected
10clinical trial searchClinicalTrials.govtetrahydrocannabinol THC cannabis treatment15 results, 5 selected
11literature searchPubMedTHC tetrahydrocannabinol psychosis cannabis schizophrenia risk10 results, 3 selected
12cross referenceCrossref API via verify_doiDOI 10.1021/ja01062a0461 result, 1 selected
13literature searchPubMedDevane Hanus anandamide isolation brain endogenous ligand cannabinoid 19921 result, 1 selected
14document retrievalPubMedD'Souza 2004 IV THC psychotomimetic effects1 result, 1 selected
15document retrievalPubMedD'Souza 2008 blunted effects frequent cannabis users1 result, 1 selected
16literature searchPubMedTHC cannabis cardiovascular effects tachycardia heart rate blood pressure3 results, 1 selected
17literature searchPubMedcannabis marijuana THC adolescent brain neurodevelopment7 results, 2 selected
18literature searchPubMedcannabinoid hyperemesis syndrome CHS2 results, 2 selected
19legal status searchWebSearchTHC DEA Schedule I classification date 1970 Controlled Substances Act10 results, 1 selected
20literature searchOpenAlexcannabis THC legalization scheduling history US8 results, 2 selected
21literature searchPubMedTHC pain analgesic neuropathic chronic controlled trial8 results, 3 selected
22legal status searchWebSearchTHC legal status UK Canada Australia New Zealand scheduling 2024 202510 results, 1 selected
23legal status searchWebSearchDEA 2024 rescheduling cannabis Schedule III proposal FDA10 results, 2 selected
24literature searchPubMedtetrahydrocannabinol PTSD post-traumatic stress disorder fear extinction treatment6 results, 2 selected
Research document (raw, unedited pipeline output)
# Research Output: Tetrahydrocannabinol (THC)

## Chemical Identity

**PubChem CID:** 16078 (verified via API — corrects blank field in brief)
**Molecular formula:** C₂₁H₃₀O₂ (verified [Ref 1 via PubChem API])
**Molecular weight:** 314.5 g/mol (verified)
**InChIKey:** CYQFCXCEBYINGO-IAGOWNOFSA-N (verified)
**IUPAC name:** (6aR,10aR)-6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydrobenzo[c]chromen-1-ol (confirmed; matches brief)
**Systematic name / common synonyms:** Δ9-THC; delta-9-tetrahydrocannabinol; (-)-trans-Δ9-tetrahydrocannabinol; dronabinol (pharmaceutical formulation name)
**CAS number:** 1972-08-3 (sourced from literature references; not directly API-verified by this pipeline run — FLAG for editorial confirmation)
**SMILES:** Not returned by PubChem API in this query — see PubChem CID 16078 for canonical SMILES (brief had blank; recommend populating from PubChem directly).

**Brief seed data assessment:** The brief contained no SMILES, molecular formula, molecular weight, PubChem CID, or InChIKey — all are now verified. The IUPAC name in the brief matches the PubChem record exactly. No discrepancies found in chemical identity data.

---

## Pharmacology

### Receptor Binding and Mechanism

THC is the primary psychoactive constituent of *Cannabis sativa*. Its principal mechanism of action is as a **partial agonist at both CB1 and CB2 cannabinoid receptors** (Pertwee 2007 [Ref 4]). Unlike synthetic full agonists (e.g., CP-55,940, HU-210), THC's partial agonism means its responses are strongly modulated by the expression level and signalling efficiency of cannabinoid receptors, as well as by ongoing endogenous cannabinoid tone [Ref 4].

**CB1 receptor (CNR1):**
- The cannabinoid receptor was first characterized in rat brain by Devane et al. 1988 [Ref 1] using the synthetic radioligand [³H]CP-55,940. In competition binding assays, Δ9-THC displaced [³H]CP-55,940 with potency lower than CP-55,940 itself but equal to 11-OH-THC: rank order CP-55,940 ≥ desacetyllevonantradol > 11-OH-Δ9-THC = Δ9-THC > cannabinol [Ref 1].
- CB1 receptors are densely expressed in the basal ganglia (substantia nigra pars reticulata, globus pallidus), hippocampus, cerebellum, and cortex (Herkenham et al. 1990 [Ref 2]; 1991 [Ref 3]). Sparse expression in the brainstem cardiorespiratory centres is the neuroanatomical basis for why lethal THC overdose does not occur via respiratory depression [Ref 2].
- The receptor is a Gi/o-coupled GPCR. Agonist binding inhibits adenylate cyclase, reduces cAMP, modulates ion channels (N- and P/Q-type calcium channels, inwardly-rectifying potassium channels), and activates MAP kinase pathways (Freund et al. 2003 [Ref 7]; Zou & Kumar 2018 [Ref 8]).
- At the network level, THC acts primarily as a **presynaptic modulator of neurotransmitter release**, suppressing both GABA and glutamate release via retrograde endocannabinoid signalling (Freund et al. 2003 [Ref 7]).
- Meta-analysis of binding affinities across phytocannabinoids confirmed Δ9-THC shows significantly higher affinity for CB1 and CB2 than CBD (Queiroz et al. 2025 [Ref 22]).

**CB2 receptor (CNR2):**
- CB2 is the peripheral cannabinoid receptor, expressed 10–100-fold more highly in immune tissues than CB1 in the CNS (Galiègue et al. 1995 [Ref 9]). THC acts as a partial agonist at CB2 [Ref 4], which may mediate immunomodulatory effects.

**Additional pharmacological targets:**
- THC activates TRPV1 (transient receptor potential vanilloid 1) channels, which may contribute to analgesic and anti-inflammatory effects (De Petrocellis et al. 2010 [Ref — OpenAlex identified; see note below]).
- THC modulates GPR55, a putative third cannabinoid receptor.
- THC inhibits anandamide cellular uptake via competition for fatty acid-binding proteins (FABPs) (Elmes et al. 2015, cited in OpenAlex but not fetched via PubMed; no Ref assigned — see Gaps).

**Dopamine system:**
Bossong et al. 2008 [Ref 14] demonstrated using PET imaging that Δ9-THC induces dopamine release in the human striatum, providing a neurochemical basis for its rewarding and reinforcing properties.

### Pharmacokinetics

Data principally from Grotenhermen 2003 [Ref 5] and Lucas et al. 2018 [Ref 6]:

**Routes of administration and bioavailability:**
- *Inhalation (smoked):* Bioavailability 10–35% (highly variable depending on cannabis potency, inhalation technique, and user experience). Peak plasma concentration achieved within 3–10 minutes. Psychotropic effects onset within seconds to a few minutes, peak at 15–30 minutes, taper within 2–3 hours [Ref 5].
- *Inhalation (vaporized):* Higher bioavailability than smoking for equivalent dose. Spindle et al. 2018 [Ref 11] showed vaporized 25mg THC produced mean peak blood THC 14.4 ng/mL vs 10.2 ng/mL for smoked; drug effects were qualitatively stronger when vaporized.
- *Oral:* Bioavailability 4–20% (high variability due to extensive first-pass hepatic metabolism and variable absorption). Psychotropic effects onset delayed 30–90 minutes; peak 2–3 hours; duration 4–12 hours depending on dose and specific effect [Ref 5]. The delayed onset and unpredictable absorption of edible cannabis is a clinically significant safety concern.
- *Intravenous:* Near-complete bioavailability, used in controlled research settings (D'Souza et al. 2004 [Ref 10]).
- *Oromucosal (Sativex):* Bioavailability intermediate between oral and inhaled.

**Distribution:** THC is highly lipophilic (logP ≈ 7) with extensive tissue distribution, particularly to adipose tissue and brain. Volume of distribution approximately 10 L/kg. Plasma protein binding 97–99%.

**Metabolism:** Primary hepatic metabolism by CYP2C9 and CYP3A4 [Ref 6; Ref 19]:
- THC → 11-hydroxy-THC (11-OH-THC) via CYP2C9/3A4 [active psychoactive metabolite; may contribute to oral THC effects]
- 11-OH-THC → 11-nor-9-carboxy-THC (THC-COOH) [inactive; the principal urinary metabolite used in drug testing]
- Both THC and CBD can inhibit CYP2C9 and CYP3A4, creating potential for drug–drug interactions (Herdegen & Cascorbi 2023 [Ref 19]).

**Elimination:** Biphasic:
- Initial (distribution) half-life: approximately 1–3 hours
- Terminal (elimination) half-life: 20–57 hours in occasional users; longer in chronic users due to adipose sequestration and slow redistribution [Ref 5]
- THC-COOH detectable in urine for days to weeks after last use (longer in chronic heavy users)

---

## History

### Discovery and Isolation

*Cannabis sativa* has been used as a medicine for millennia. The earliest documented uses trace to the Vedic foundational texts of Ayurvedic medicine (~800 BCE) and the Chinese pharmacopoeia *Shen Nung Pen Ts'ao Ching* (1st century BCE) (Pisanti & Bifulco 2019 [Ref 30]; Russo 2007 [Ref 31]). Uses in ancient Egypt for analgesia, anti-inflammatory, and anticonvulsant purposes are also documented [Ref 31].

The psychoactive constituent of cannabis was identified by **Yechiel Gaoni and Raphael Mechoulam** at the Weizmann Institute of Science in Israel. Their landmark 1964 paper in the *Journal of the American Chemical Society* — "Isolation, Structure, and Partial Synthesis of an Active Constituent of Hashish" — established the molecular structure and partial synthesis of delta-9-THC (Gaoni & Mechoulam 1964 [Ref 23]). This was the culmination of work on the pharmacologically active fraction of cannabis resin.

### Development of the Endocannabinoid System

- 1988: Devane, Dysarz, Johnson, Melvin & Howlett characterized the specific cannabinoid receptor (CB1) in rat brain using [³H]CP-55,940, demonstrating G-protein coupling and pharmacological specificity [Ref 1].
- 1990: Herkenham et al. mapped cannabinoid receptor localization across mammalian brain [Ref 2].
- 1991: Matsuda et al. cloned the CB1 receptor (not directly retrieved in this run — see Gaps); Herkenham et al. published quantitative autoradiographic characterization [Ref 3].
- 1992: Devane, Hanus, and Mechoulam et al. discovered **anandamide** (arachidonylethanolamide) as the first endogenous cannabinoid ligand in porcine brain [Ref 24].
- 1993: Munro, Thomas & Abu-Shaar cloned the CB2 receptor (not directly retrieved in this run — see Gaps).
- 1995: Galiègue et al. characterized CB1 and CB2 distribution in human immune tissues [Ref 9].

### Clinical / Regulatory History

- **1985:** FDA approved **dronabinol (Marinol)** — synthetic THC in sesame oil — for chemotherapy-induced nausea and vomiting (CINV) refractory to other antiemetics (Todaro 2012 [Ref 17]).
- **1992:** Dronabinol received additional FDA approval for anorexia/weight loss in AIDS patients.
- **~2005–2010:** **Nabiximols (Sativex)**, a standardized oromucosal spray containing THC and CBD in approximately 1:1 ratio, approved in Canada (2005), then UK and other European and international markets for MS spasticity and pain (Pagano et al. 2022 [Ref 40]).
- **1970:** Cannabis and THC placed in Schedule I of the US Controlled Substances Act [Ref 41].
- **2024–2026:** US rescheduling process: HHS recommended Schedule III reclassification in August 2023; DEA issued proposed rule May 2024 [Ref 47]; in April 2026, DOJ issued an order placing FDA-approved marijuana products and products regulated under qualifying state medical marijuana licenses in Schedule III, with a broader rescheduling hearing scheduled for June 2026 [Ref 48].

---

## Subjective Effects

Based on controlled human studies:

### Controlled dose-response data

**D'Souza et al. 2004 [Ref 10]** (3-day double-blind, randomized, placebo-controlled crossover; IV THC 0, 2.5, 5 mg; n=22 healthy individuals with prior cannabis exposure but no CUD):
- *Positive effects:* Euphoria (dose-dependent), increased subjective "high"
- *Psychotomimetic effects:* Schizophrenia-like positive symptoms (hallucinations, conceptual disorganization, suspiciousness/paranoia), negative symptoms (blunted affect, emotional withdrawal, psychomotor retardation)
- *Perceptual alterations:* Time distortion, visual and sensory changes
- *Anxiety:* Increased anxiety at both doses
- *Cognitive:* Disrupted immediate and delayed word recall (recognition recall spared), impaired distractibility/verbal fluency/working memory; orientation intact
- *Endocrine:* Increased plasma cortisol
- *Cardiovascular:* Tachycardia

**Spindle et al. 2018 [Ref 11]** (within-participant, double-blind crossover; smoked and vaporized 0, 10, 25 mg THC; n=17 infrequent cannabis users):
- 10 mg: Discriminative drug effects (smoked: 46/100; vaporized: 69/100), modest cognitive impairment
- 25 mg: Significant drug effects (smoked: 66/100; vaporized: 78/100), increased adverse effects, pronounced psychomotor and cognitive impairment
- Blood THC and heart rate peaked within 30 minutes; returned to baseline within 3–4 hours
- Subjective and cognitive impairment effects persisted up to 6 hours
- Vaporized produced qualitatively stronger effects than equal smoked dose

**Grotenhermen 2003 [Ref 5]** (review of clinical studies): At doses exceeding the psychotropic threshold, effects include enhanced well-being and relaxation with intensification of ordinary sensory experiences.

### Key effect domains documented in literature

The following effects map onto the Psychedex taxonomy:
- **Euphoria** [Ref 10; Ref 5]
- **Anxiety / Paranoia** [Ref 10; Ref 36 — Crippa 2009 systematic review]
- **Appetite enhancement** (endocannabinoid/hypothalamic mechanism; Kirkham et al. 2002 [OpenAlex — not individually ref-linked])
- **Sedation / Bodily heaviness** [Ref 5]
- **Dry mouth** (common adverse event: 3.2% in UK Medical Cannabis Registry [Ref 39])
- **Tachycardia / Heart rate perception changes** [Ref 10; Ref 45]
- **Dizziness** (2.2% in UKMCR [Ref 39])
- **Memory fragmentation / Amnesia** [Ref 10; Ref 26]
- **Cognitive impairment / Focus suppression** [Ref 37 — Ramaekers 2006; Ref 11]
- **Thought disorganization / Confusion** [Ref 10]
- **Time alteration** [Ref 5]
- **Visual distortions / perceptual alterations** [Ref 10]
- **Music enhancement, taste enhancement** (commonly reported by users; limited controlled study data specifically for these)
- **Depersonalization / Derealization** (at higher doses; [Ref 10 positive/negative symptoms overlap])
- **Laughter fits** (user reports; not systematically studied in controlled trials)

**Dose-duration summary (from published literature — for editorial review and structured data proposal):**

*Smoked/inhaled:*
- Threshold: ~1–2 mg THC
- Light: 2–5 mg
- Common: 5–15 mg
- Strong: 15–25 mg+
- Onset: seconds to 3 minutes; Peak: 15–30 minutes; Duration: 2–3 hours [Ref 5]

*Oral:*
- Threshold: ~2–5 mg
- Light: 5–10 mg
- Common: 10–20 mg
- Strong: 20–50 mg+
- Onset: 30–90 minutes; Peak: 2–3 hours; Duration: 4–12 hours [Ref 5]

⚠️ FLAG: These dose ranges are derived from the Grotenhermen 2003 review and the D'Souza/Spindle controlled studies. The brief contains no existing dose data. These values are from published literature and should go through the editorial dose review process before population in the DB.

---

## Safety & Toxicity

### Lethal dose / Overdose

**No confirmed human fatalities from THC overdose alone.** The neuroanatomical basis for this is well established: cannabinoid receptor density in the brainstem areas controlling cardiovascular and respiratory function is very sparse (Herkenham et al. 1990 [Ref 2]). This is in stark contrast to opioid receptors, which are densely expressed in the brainstem.

In animals: LD50 in rodents is very high (rats oral LD50 estimated 800–1900 mg/kg from early toxicology literature; species-dependent). These values are from pre-digital animal pharmacology studies not directly retrieved via API. FLAG: Specific LD50 values not API-verified in this research run.

The theoretical LD50-to-active dose ratio (therapeutic index) for THC is exceptionally high — estimates of >1000:1 are cited in reviews (Herkenham 1990 [Ref 2]; Grotenhermen 2003 [Ref 5]).

### Acute adverse events

Documented in clinical trials and registry data:
- **Tachycardia** — consistent and well-documented; cardiac index increase reported at IV doses (Malit et al. 1975, PMID 1130738; Benowitz & Jones 1975 [Ref 45])
- **Orthostatic hypotension** — seen acutely; with prolonged use, tolerance develops [Ref 45]
- **Anxiety / Panic reactions** — most important acute adverse effect according to Grotenhermen 2003 [Ref 5]; dose-dependent
- **Psychotomimetic symptoms** — dose-dependent (D'Souza 2004 [Ref 10])
- **Nausea** (3.8% in UKMCR [Ref 39])
- **Dizziness** (2.2% in UKMCR [Ref 39])
- **Somnolence** (2.2% in UKMCR [Ref 39])
- **Cognitive impairment** — acute, dose-dependent; high-potency cannabis associated with executive function and motor control impairment (Ramaekers et al. 2006 [Ref 37])

### Psychosis and psychiatric risk

This is the most significant documented safety concern for THC. Evidence is robust:
- Di Forti et al. 2019 [Ref 25] (EU-GEI multicentre case-control, n=901 first-episode psychosis + 1237 controls): Daily cannabis use OR 3.2 for psychotic disorder; **daily use of high-potency cannabis (THC ≥10%) OR 4.8**. If high-potency cannabis unavailable, 12.2% of first-episode psychosis cases preventable across 11 European sites.
- D'Souza et al. 2004 [Ref 10]: IV THC produces positive and negative schizophrenia-like symptoms in healthy individuals in a dose-dependent fashion.
- Cannabis exposure during adolescence confers substantially higher psychosis risk (Hoch et al. 2025 [Ref 15]; Murphy et al. 2017 [Ref 49]).
- THC use is contraindicated in individuals with personal or family history of psychotic disorders (Lucas et al. 2018 [Ref 6]).

### Cannabinoid Hyperemesis Syndrome (CHS)

A paradoxical syndrome seen in chronic heavy cannabis users, characterized by cyclic nausea and vomiting with compulsive hot bathing for relief (Stjepanovic et al. 2025 [Ref 27]). Standard antiemetics are typically ineffective. Cases appear to have increased following cannabis legalization. Fatal cases reported (Nourbakhsh et al. 2019 [Ref 28]).

### Respiratory effects (smoking route)

Chronic cannabis smoking is associated with symptoms of chronic bronchitis (cough, sputum production, wheezing), impaired alveolar macrophage function, and potential for increased respiratory infection susceptibility. Unlike tobacco, cannabis smoking does not consistently cause emphysema (Georgakopoulou et al. 2025 [Ref 46]). Vaporization appears to reduce (but not eliminate) these risks.

### Cardiovascular effects

Acute tachycardia is consistent and well-documented. THC also causes orthostatic hypotension acutely. Chronic administration with prolonged use leads to tolerance of these effects (Benowitz & Jones 1975 [Ref 45]). Cannabis is contraindicated in significant cardiovascular disease (Lucas 2018 [Ref 6]).

### Prenatal / developmental toxicity

THC crosses the placenta and accumulates in breast milk (Wymore et al. 2025 [Ref 29]). Associated with lower birth weight and potential neurodevelopmental risk in offspring, though evidence is complicated by confounders (Reck et al. 2025). ACOG and AAP strongly advise against use during pregnancy and breastfeeding [Ref 29]. Adolescent exposure associated with long-term cognitive impairment and psychiatric vulnerability [Ref 49].

### Driving impairment

THC acutely impairs psychomotor performance relevant to driving. However, blood THC concentrations are poorly correlated with magnitude of impairment, making per se legal limits problematic (Arkell et al. 2021 [Ref 38]).

---

## Harm Reduction

Published evidence supports the following risk reduction strategies:

1. **Avoid high-potency products:** The strongest evidence for psychiatric risk is tied to daily use of cannabis with THC ≥10%. Reducing THC potency reduces psychosis risk (Di Forti 2019 [Ref 25]).
2. **Start low, go slow:** Particularly important for oral/edible routes due to delayed onset and variable absorption (Lucas 2018 [Ref 6]). The delayed onset of edibles (30–90 min) frequently leads to redosing before the initial dose has taken full effect.
3. **Vaporization over combustion:** Reduces respiratory harm (Georgakopoulou 2025 [Ref 46]; Chaiton et al. 2026).
4. **Avoid use during adolescence:** Adolescent brain is particularly vulnerable to adverse neurodevelopmental outcomes (Murphy et al. 2017 [Ref 49]; Hoch et al. 2025 [Ref 15]).
5. **Avoid use in psychosis-vulnerable individuals:** Personal/family history of psychotic disorder is a strong contraindication (Lucas 2018 [Ref 6]; Kapler et al. 2024).
6. **Avoid use in pregnancy/breastfeeding** (Wymore et al. 2025 [Ref 29]).
7. **Contraindicated in:** Significant cardiovascular, pulmonary, hepatic, or renal illness; active psychotic disorder; concurrent use of other CNS depressants should be approached with caution (Lucas 2018 [Ref 6]; Gorelick & Heishman 2006 [Ref 44]).
8. **CBD may partially attenuate some THC adverse effects:** Some evidence from animal models; clinical human data remain inconclusive (de Bode et al. 2025 [Ref 50]; Ertl et al. 2024 showed CBD did not counteract and sometimes potentiated THC effects on brain connectivity).

**Testing:** Street cannabis cannot be easily tested for THC concentration without laboratory equipment; fentanyl test strips are not relevant. High-performance liquid chromatography (HPLC) or gas chromatography (GC) is used for potency determination in regulated markets.

---

## Tolerance & Dependence

### Tolerance

Tolerance to THC develops through well-characterized mechanisms:
- **CB1 receptor desensitization** (GRK phosphorylation of serine residues S426 and S430 → β-arrestin recruitment → uncoupling from G-protein)
- **CB1 receptor downregulation** (decreased receptor expression with prolonged agonist exposure)
- These changes begin within days of regular heavy use; reverse over 2–4 weeks of abstinence (Bonnet & Preuss 2017 [Ref 12])
- Importantly, tolerance is differential: D'Souza et al. 2008 [Ref 26] found frequent users are tolerant to the psychotomimetic, perceptual, cognitive, anxiogenic, and cortisol-elevating effects of IV THC but **NOT to its euphoric effects** — a pattern clinically significant for addiction liability.

**Cross-tolerance:** Tolerance to THC produces cross-tolerance to other CB1 agonists.

### Dependence and Cannabis Use Disorder

- Approximately **9% of all cannabis users** develop dependence (Hood 2018, PMID 30193704; Hasin 2017 [Ref 35]).
- Risk increases to approximately 17% among those who begin in adolescence.
- **Cannabis withdrawal syndrome** occurs in approximately **50% of regular and dependent users** upon cessation (Connor et al. 2022 [Ref 13]).
- Withdrawal symptoms: irritability/anger/aggression, anxiety, insomnia, decreased appetite/weight loss, restlessness, depressed mood, physical symptoms (tremors, sweating, abdominal pain, headache). Onset typically within 24–48 hours of cessation; peak 2–3 days; duration 1–2 weeks (Bonnet & Preuss 2017 [Ref 12]).
- **No FDA-approved pharmacotherapy for CUD** (Spiga et al. 2025 Cochrane [Ref 16]). Nabiximols (THC+CBD) has shown evidence for reducing withdrawal symptoms in dependent users (Trigo et al. 2018, PMID 29385147).

---

## Interactions

### Pharmacokinetic interactions (CYP enzymes)

- THC is a substrate of **CYP2C9** (primary) and **CYP3A4**
- Both THC and CBD are **inhibitors of CYP2C9 and CYP3A4**, creating the potential for increased plasma concentrations of co-administered drugs metabolized by these enzymes
- Published example: CBD inhibits clobazam metabolism, increasing active metabolite levels (Lucas 2018 [Ref 6]; Herdegen & Cascorbi 2023 [Ref 19])
- CYP induction by chronic cannabis use may reduce efficacy of some co-administered drugs (Mann et al. 2026 [Ref 21] notes potential for increased propofol requirements in chronic users)

### Pharmacodynamic interactions

- **CNS depressants** (alcohol, benzodiazepines, opioids, sedating antihistamines): Additive CNS depression, sedation, psychomotor impairment (Lucas 2018 [Ref 6])
- **Sympathomimetics:** Additive tachycardia and hypertension (Lucas 2018 [Ref 6])
- **Antipsychotics:** THC may antagonize or reduce efficacy; THC can exacerbate psychosis in those with schizophrenia spectrum disorders
- **Anticholinergics:** Additive tachycardia, dry mouth, cognitive impairment

### Contraindications

- Significant psychiatric illness (particularly psychotic disorders) [Ref 6; Ref 25]
- Significant cardiovascular disease [Ref 6]
- Pregnancy and breastfeeding [Ref 29]
- Significant pulmonary disease [Ref 46]
- Active substance use disorder (risk of exacerbation) [Ref 15]
- Concurrent use with other intoxicants in dose-sensitive contexts (driving, machinery) [Ref 38]

---

## Legal Status

**United States:**
- Cannabis and THC have been in **Schedule I** of the Controlled Substances Act since its enactment in 1970 [Ref 41].
- Dronabinol (pharmaceutical-grade THC) was placed in Schedule III in 1999 (CAS 1972-08-3 in sesame oil formulation).
- In August 2023, HHS recommended reclassification to Schedule III; in May 2024, DEA issued a Notice of Proposed Rulemaking (NPRM) to move marijuana to Schedule III [Ref 47].
- In **April 2026**, the DOJ issued an order placing **FDA-approved marijuana products and products regulated under qualifying state medical marijuana licences in Schedule III**. An expedited hearing for broader rescheduling of all marijuana is scheduled to begin June 29, 2026 [Ref 48].
- Cannabis remains a Schedule I substance at federal level for non-FDA-approved and non-state-licensed products as of this research date (May 2026).
- The 2018 Farm Bill defined hemp as *Cannabis sativa* with <0.3% Δ9-THC by dry weight, creating a legal distinction.

**International:**
- **UN Single Convention on Narcotic Drugs (1961):** Cannabis listed in Schedules I and IV (most restrictive). In December 2020, the UN Commission on Narcotic Drugs voted to remove cannabis from Schedule IV but retain it in Schedule I.
- **Canada:** Legal for recreational and medical use since the *Cannabis Act* (2018). Adults may possess up to 30g.
- **United Kingdom:** THC is a **Class B controlled drug** under the Misuse of Drugs Act 1971. CBD products are permitted but limited to 1 mg THC per product container.
- **Australia:** Medical cannabis approved by the Therapeutic Goods Administration (TGA) for certain indications; THC-containing products require prescription. No legal recreational use at federal level, though several states/territories have decriminalized possession.
- **Germany:** Recreational cannabis legalized for adults in April 2024 (up to 25g possession, limited home cultivation).
- **Netherlands:** Tolerated recreational use under gedoogbeleid (tolerance policy); technically illegal but possession of small amounts (≤5g) and coffee shop sales are not prosecuted.
- **New Zealand:** Medical use legal with prescription; recreational use remains illegal.

---

## Clinical Trials

Key trials retrieved from ClinicalTrials.gov:

| NCT ID | Title | Phase | Status | Relevance |
|--------|-------|--------|--------|-----------|
| NCT04080427 | Effects of THC on Retention of Memory for Fear Extinction in PTSD (R33) | Phase 1 | Completed | THC for PTSD fear extinction learning |
| NCT05052541 | Safety and Efficacy of Oral Cannabis in Chronic Spine Pain | Phase 3 | Recruiting | Phase 3 RCT for chronic pain indication |
| NCT01606137 | Long-term Safety Study of Sativex (nabiximols) | Phase 3 | Completed | Long-term safety of THC+CBD oromucosal spray in MS |
| NCT01323569 | Abuse Potential of Sativex | Phase 1 | Completed | Abuse liability characterization |
| NCT04201197 | Cannabinoids and Cytochrome P450-Metabolized Drugs | Phase 1 | Completed | Drug interaction profile at CYP450 level |
| NCT04883255 | Cannabis Use, Cognition, and the Endocannabinoid System in HIV | Early Phase 1 | Recruiting | Cognitive effects in HIV+ cannabis users |

---

## Community Feedback Analysis

No community feedback was submitted for this substance (brief Part A2 is empty).

---

## Gaps & Flags

### Verified data points absent from brief that are now confirmed:
- PubChem CID (16078), molecular formula (C₂₁H₃₀O₂), molecular weight (314.5 g/mol), InChIKey (CYQFCXCEBYINGO-IAGOWNOFSA-N): All verified via API.
- SMILES: Not returned by the PubChem API call in this run. Recommend pulling canonical SMILES directly from PubChem CID 16078.

### Data points that could not be verified or require editorial attention:

1. **CAS number (1972-08-3):** Sourced from cross-referencing literature. Not directly confirmed via PubChem API in this run. FLAG: editorial verification recommended.

2. **Specific Ki values for THC at CB1 and CB2:** No published primary binding study with specific Ki (nM) values for Δ9-THC was directly retrieved via PubMed in this run. The Devane 1988 paper [Ref 1] gives relative order of potency but not absolute Ki for THC specifically. The Queiroz et al. 2025 meta-analysis [Ref 22] confirmed significantly higher affinity than CBD but did not quote a specific Ki value in the abstract. FLAG: generation agent should note that specific Ki values for THC at CB1/CB2 are not confirmed from this research run and should source from a primary binding affinity table (e.g., Pertwee 2008 Handbook of Experimental Pharmacology).

3. **THC LD50 (animal):** Referenced in the literature as very high (800–1900 mg/kg oral in rats) from early toxicology studies, but these pre-digital papers were not API-verified in this run. FLAG: safety-critical value not confirmed by verified source.

4. **Specific bioavailability percentages:** Grotenhermen 2003 [Ref 5] cites ranges (10–35% smoked, 4–20% oral) from primary PK studies not individually verified in this run. These are well-cited review figures but the underlying Huestis pharmacokinetics studies (e.g., Huestis et al. 1992 *Chem Res Toxicol*) were not individually fetched.

5. **CB1 and CB2 receptor cloning papers:** Matsuda et al. 1990 (*Nature*, CB1 cloning) and Munro et al. 1993 (*Nature*, CB2 cloning) are landmark papers referenced throughout the literature but were not directly retrieved via PubMed API in this run (likely due to query specificity). These should be added to the registry by the generation agent if available.

6. **THC biosynthesis / plant chemistry:** Not covered in this research run; generation agent should draw on André et al. 2016 [Ref 18] for plant phytochemistry context.

7. **Germany recreational legalization (April 2024):** Sourced from web knowledge; not API-verified via a primary legal document.

8. **Dose ranges (brief has no existing dose data):** The proposed dose ranges in the Subjective Effects section are derived from Grotenhermen 2003 [Ref 5] and the D'Souza/Spindle controlled studies. These should be treated as literature-based proposals for editorial dose review, not as confirmed DB values.

9. **THC characterization in brief is listed as "emerging":** Given that THC is arguably the most well-studied psychoactive compound in pharmacological history, "emerging" is almost certainly a data entry error. FLAG: editorial attention — characterization should likely be "well-characterized" or "classic."

10. **Primary ROA and Known ROAs:** Not in the brief. Primary ROA is inhalation (smoked or vaporized); known ROAs include inhalation, oral, sublingual/oromucosal, rectal (suppositories), intravenous (research only), transdermal (in development). FLAG: these fields should be populated.