AB-FUBINACA
Viewing r1 — May 11, 2026 — CURRENT
Back to HistoryInteractions, related substances, and reports reflect the current entry and are not shown for historical revisions.
AB-FUBINACA is a synthetic cannabinoid of the indazole-3-carboxamide class. It is far more potent than cannabis — a full agonist at cannabinoid receptors where cannabis's active compound only partially activates them.[1] It drives those receptors to maximum intensity, producing the dense sedation and perceptual disruption characteristic of potent synthetic cannabinoids.
Psychedex is in open beta. We are still fine-tuning the generation and review process. Please double-check sources.
Pfizer synthesized it in 2009 as a candidate painkiller, but it was never developed into a medicine.[2] It surfaced in illicit herbal smoking blends in Japan in 2012[3] and spread rapidly across global drug markets. It is now controlled in most major jurisdictions worldwide.
Subjective effects include sedation, heavy cognitive impairment, confusion, hallucinations, and agitation.[4] Smoked, it hits almost immediately — a dense, disorienting intoxication with no self-limiting ceiling.[5] Cardiovascular disruption, acute psychological distress, and severe confusion are characteristic unwanted effects.[6]
AB-FUBINACA produces physical dependence in animals, and no lethal dose has been established in any species.[5] Full agonism removes the ceiling on cannabinoid receptor activation, and unusually slow clearance prolongs exposure — animal studies show brain damage, kidney injury, and reproductive harm with repeated dosing.[7][8][9] No controlled human studies exist — what is known comes from animal research, forensic casework, and emergency clinical reports.
History[edit]
Discovery
AB-FUBINACA was synthesized by Pfizer in 2009 as part of a cannabinoid pain research program. It was disclosed in patent WO2009/106982[1] but never advanced to human testing.
Illicit emergence and scheduling
It first appeared in seized herbal smoking blends in Japan in 2012, identified by researchers at the National Institute of Health Sciences.[3] Japan became the first country to schedule it in December 2012. The compound then spread across European, North American, and Asian markets — prompting US temporary Schedule I placement in 2014 and permanent scheduling in September 2016.[2]
Present status
AB-FUBINACA is now controlled in most major jurisdictions. It was added to Schedule II of the 1971 UN Convention on Psychotropic Substances in 2020,[10] obligating signatory nations to implement controls. Its scheduling drove demand toward newer, unscheduled synthetic cannabinoid analogs — a pattern that repeats with every ban.
The name AB-FUBINACA follows synthetic cannabinoid naming conventions: AB denotes the amino acid side chain (from L-valine), FUB refers to the 4-fluorobenzyl substituent, and INACA indicates the indazole-carboxamide scaffold.
Chemistry[edit]
Structural class
AB-FUBINACA belongs to the indazole-3-carboxamide family of synthetic cannabinoids. Its structure combines an indazole core with a 4-fluorobenzyl group and an L-valinamide side chain,[1] placing it alongside related compounds including AB-PINACA, ADB-FUBINACA, and AMB-FUBINACA.
Molecular properties
| Molecular formula | C₂₀H₂₁FN₄O₂ |
| Molecular weight | 368.4 g/mol |
The fluorine atom in the benzyl ring helps AB-FUBINACA resist liver breakdown — in lab studies, most of the parent compound remained intact after three hours of exposure to human liver enzymes.[12] Illicit synthesis can also produce positional isomers — structural variants with the same atoms arranged slightly differently — that remain active but are less potent than the correct form.[13]
Pharmacology[edit]
Mechanism of action
AB-FUBINACA is a full agonist at cannabinoid receptors, especially CB1.[1] Cannabis's Δ9-THC only partially activates those receptors — AB-FUBINACA drives them to maximum output, removing the self-limiting ceiling on effects. It surpasses earlier synthetic cannabinoids like JWH-018 in potency,[14] and animal studies confirm that CB1 alone drives its cannabinoid effects.[15]
Pharmacokinetics
No controlled human study exists. In lab tests with human liver tissue, 77% of AB-FUBINACA remained intact after three hours — far higher than most synthetic cannabinoids, consistent with unusually slow clearance.[12]
In one heavy user monitored during abstinence, metabolites were detectable in urine for over two years after last use.[16] This extended elimination means urine tests cannot reliably confirm recent abstinence in former heavy users.
Neuroscience[edit]
Where it acts
CB1 receptors normally act as a feedback dial — receiving neurons release endocannabinoids to quiet overactive signaling. AB-FUBINACA keeps those receptors permanently on, bypassing the feedback system and forcing continuous disruption of brain activity. In mice, repeated exposure damages the hippocampus — causing oxidative stress, inflammation, cell death, and measurable impairment of memory.[7]
Why it matters
That hippocampal damage includes a reduction in glutamate receptor activity[7] — a signaling pathway strongly linked to schizophrenia-spectrum disorders. Whether this translates to lasting psychosis risk in humans is unknown — no study has tracked it.
Cardiovascular effects are unpredictable in direction: tachycardia in some,[6] slowed heart rate and low blood pressure in others.[17] This likely reflects dose-dependent shifts in autonomic nervous system balance.[15]
- Does the hippocampal glutamate receptor reduction seen in mice[7] translate to psychosis vulnerability in humans? No longitudinal study has tracked psychosis incidence in AB-FUBINACA-exposed populations.
- Is the extraordinarily prolonged urinary retention[16] pharmacologically meaningful — does tissue-stored compound maintain low-level CB1 activation during the extended elimination phase, or is the retained material inert?
Subjective Effects[edit]
AB-FUBINACA delivers a heavy, fast-moving cannabinoid experience. Smoked, the onset is nearly immediate — consciousness shifts into dense sedation, cognitive fog, and perceptual distortion compressed into a short window. The experience is highly unpredictable: identical doses have produced drowsy calm in some and severe agitation with hallucinations in others.[4]
Cannabis's partial agonism at cannabinoid receptors creates a natural ceiling on effects. AB-FUBINACA's full agonism removes that ceiling entirely.[5] Its intensity and risk profile sit closer to potent synthetic cannabinoids like JWH-018 than to plant cannabis, despite sharing the same receptor target.
Effect Grid
The full cannabimimetic profile manifests — sedation dominates, accompanied by pronounced thought deceleration, analysis suppression, and cognitive impairment. Immersion enhancement and conceptual thinking may emerge. Anxiety and paranoia are possible, particularly in unfamiliar settings or anxious individuals. Spontaneous body sensations and vestibular distortion contribute to a notable altered state.
Physical effects include marked bodily heaviness, motor control impairment, dry mouth, appetite enhancement, and nausea in some users. Cardiovascular effects become possible — heart rate changes in either direction (tachycardia or bradycardia) may occur unpredictably.
Duration spans approximately 1–2 hours total. This is a full agonist with no ceiling effect — the dose-response curve is steeper and less forgiving than cannabis.
Modeled from the effect's dose-dependence curve — not per-substance measurements.
Depth perception distortion · Proprioceptive distortion · Visual acuity suppression · Visual haze / noise · Color enhancement · Perspective distortion · Sound sensitivity · Taste enhancement · Touch enhancement · Brightness alteration · Color alteration · Auditory distortion · Auditory misinterpretation · Geometry · Visual processing suppression · Auditory hallucinations · External hallucinations · Internal hallucinations · Visual recursion
Color enhancement · Perspective distortion · Sound sensitivity · Taste enhancement · Touch enhancement · Brightness alteration · Color alteration · Auditory distortion · Auditory misinterpretation · Geometry · Visual processing suppression · Auditory hallucinations · External hallucinations · Internal hallucinations · Visual recursion
Bodily heaviness · Dizziness · Heart rate perception changes · Physical fatigue · Appetite enhancement · Spontaneous body sensations · Muscle relaxation · Dehydration sensation · Laughter fits · Tactile euphoria · Nausea · Pain suppression · Breathing alteration · Constipation · Excessive sweating · Headache · Restlessness · Trembling · Vomiting · Involuntary body movements · Nausea suppression
Appetite enhancement · Spontaneous body sensations · Muscle relaxation · Dehydration sensation · Laughter fits · Tactile euphoria · Nausea · Pain suppression · Breathing alteration · Constipation · Excessive sweating · Headache · Restlessness · Trembling · Vomiting · Involuntary body movements · Nausea suppression
Analysis suppression · Cognitive fatigue · Confusion · Focus suppression · Information processing suppression · Immersion enhancement · Memory fragmentation · Thought disorganization · Thought connectivity · Aesthetic enhancement · Cognitive dysphoria · Cognitive euphoria · Language suppression · Motivation suppression · Novelty enhancement · Humor enhancement · Conceptual thinking · Pattern recognition enhancement · Thought loops · Creativity enhancement · Amnesia · Delusions · Delirium
Focus suppression · Information processing suppression · Immersion enhancement · Memory fragmentation · Thought disorganization · Thought connectivity · Aesthetic enhancement · Cognitive dysphoria · Cognitive euphoria · Language suppression · Motivation suppression · Novelty enhancement · Humor enhancement · Conceptual thinking · Pattern recognition enhancement · Thought loops · Creativity enhancement · Delusions · Delirium
Dysphoria · Irritability · Anxiety suppression
Sociability suppression · Craving · Disinhibition · Sociability enhancement · Cognitive disconnection
Cognitive disconnection
Timeline
Rapid absorption via pulmonary route; effects emerge within seconds to minutes. Initial body sensation changes and a cognitive shift begin. First alerts of altered sensorium are typically felt within the first few minutes.
Maximum intensity — sedation, cognitive impairment, bodily heaviness, and cardiovascular effects reach their strongest. Anxiety, paranoia, and perceptual disturbances are most likely during this phase. Full agonist pharmacology means no ceiling on intensity.
Relatively rapid decline in subjective effects. Sedation begins to lift and cognitive function starts to return. Motor impairment and mild cognitive fog may linger beyond the perceived end of the peak.
Residual sedation and mild cognitive fog. Most acute effects have resolved. Appetite changes may persist.
Safety[edit]
- Acute toxicity
- High
- Chronic toxicity
- High
- Withdrawal
- Moderate
- Tolerance buildup
- moderate
- Tolerance reset
- 1.5 weeks
- Physical
- Moderate
- Psychological
- Moderate
- Compulsive redosing
- Moderate
- Dose escalation
- Moderate
- Cross-tol.
- cannabinoids
Toxicity
No lethal dose has been established in any species. The toxic threshold in humans is unknown.
Acute toxicity
Acute intoxication causes altered consciousness, agitation, drowsiness, hallucinations, and cognitive impairment.[4] Heart rate effects are unpredictable in direction — rapid heart rhythm has been documented in a case involving AB-FUBINACA and ADB-FUBINACA,[6] while slow heart rate and low blood pressure appeared in separate case series.[17]
At least one fatality has been documented: AB-FUBINACA combined with the synthetic opioid U-47700.[18] The relative contribution of each substance is unresolved.
AB-FUBINACA has been found as an adulterant in unregulated drug supplies, including products not sold as synthetic cannabinoids.[19] People using other substances may be exposed without knowing. The combination with opioids is particularly dangerous given documented fatality data.[18]
Brain toxicity
Repeated exposure in mice damages memory-related brain regions — causing oxidative stress, inflammation, cell death, and measurable memory suppression.[7] No human brain data exist.
Kidney toxicity
Mouse studies show kidney damage consistent with acute kidney injury.[8] Acute kidney injury has been reported with synthetic cannabinoids broadly in humans,[20] though no AB-FUBINACA-specific human case has been published.
Reproductive toxicity
Repeated dosing in mice impairs male fertility and causes testicular tissue damage.[9] No human reproductive data exist.
DNA damage
AB-FUBINACA damages DNA in cultured human white blood cells at laboratory concentrations.[21] Two structurally related compounds showed similar effects.[21] Laboratory DNA damage does not directly predict cancer risk but warrants caution about long-term exposure.
Psychological Risks
Confusion, agitation, hallucinations, delusions, and severely impaired reality testing are consistent features of intoxication.[4][6] These exceed what cannabis produces because full CB1 agonism removes the ceiling on psychotomimetic effects.
High-potency CB1 full agonists carry elevated psychosis risk compared to cannabis.[22] Whether AB-FUBINACA triggers lasting psychotic disorders has not been studied. The receptor changes seen in chronically exposed mice[7] offer a plausible biological mechanism but do not confirm this in humans.
Tolerance and Dependence
Physical dependence develops in mice with repeated dosing, demonstrated through withdrawal when the drug is abruptly removed.[5] High-potency CB1 full agonists downregulate receptors more readily than partial agonists, so tolerance builds faster than with cannabis.
The urinary detection window may exceed one year in heavy users[16] — meaning a positive drug test cannot reliably distinguish recent use from residual clearance.
Drug Interactions
No controlled interaction studies exist.
Opioids are the most clearly documented hazard. A fatality involving AB-FUBINACA and the synthetic opioid U-47700 has been documented,[18] and AB-FUBINACA has appeared as an adulterant in unregulated supplies.[19] The combination deepens nervous system and breathing depression additively.
Cannabis and other CB1 agonists produce additive receptor activation, worsening sedation, cognitive impairment, and psychosis risk.
Sedatives (benzodiazepines, alcohol, barbiturates) are expected to add to sedation and respiratory depression. No AB-FUBINACA-specific data exist.
Certain liver enzyme inhibitors (ketoconazole, ritonavir, clarithromycin) may raise AB-FUBINACA blood levels by slowing clearance; inducers (rifampicin, carbamazepine, St. John's Wort) may lower them. Both effects are inferred from structural analogy and have not been clinically confirmed.[23] inferred
Contraindications
- Heart rhythm disorders or structural heart disease — cardiovascular effects are unpredictable in direction.[6]
- Psychotic disorders or high psychosis risk — all high-potency CB1 full agonists carry elevated psychosis risk compared to cannabis.[22] Personal or family history of psychotic disorders is an absolute contraindication.
- Kidney disease — animal data show kidney toxicity,[8] and synthetic cannabinoids broadly are associated with acute kidney injury in humans.[20]
- Pregnancy and breastfeeding — animal studies show male reproductive toxicity,[9] and DNA damage has been demonstrated in human cell cultures.[21]
- Concurrent opioid use — a fatality involving this combination has been documented.[18]
Harm Reduction[edit]
Forms & Identification
AB-FUBINACA typically appears in herbal smoking blends — dried plant material sprayed with a solution of the compound. Concentration varies dramatically within a single product. Hotspots of concentrated material on one part of a leaf can deliver a dose many times higher than adjacent material from the same package.
Standard cannabis drug tests will not reliably detect synthetic cannabinoids. Specialized synthetic cannabinoid panels or laboratory mass spectrometry are required for confirmation.
Guidelines
- Test all material with reagent kits and, where available, laboratory drug checking services — visual inspection cannot distinguish AB-FUBINACA from other synthetic cannabinoids or herbal blends.
- Start with the smallest possible amount. Hotspot distribution in sprayed herbal products means no two portions from the same batch are equivalent.
- Have a sober, trusted person present who knows what was taken and can call for help if needed.
- Do not redose during the active window. The short duration creates an compulsive redosing urge that can rapidly produce toxicity.
- Keep the environment calm, quiet, and temperature-controlled — AB-FUBINACA affects body temperature regulation.
- Do not use alone. Loss of consciousness and cardiovascular events have been documented with synthetic cannabinoids.
Set & Setting
The fast onset and unpredictable intensity of AB-FUBINACA make environment critical. A familiar, safe indoor space with a sober companion is the minimum reasonable precaution. Avoid any situation requiring coordination, driving, or complex decision-making — there is minimal time to adjust once the experience begins.
Aftercare & integration. The short active duration of AB-FUBINACA can leave users feeling disoriented or anxious in the hours following exposure. Rest in a calm environment, eat when appetite returns, and hydrate. Avoid driving or operating machinery for at least several hours after effects resolve.
If the experience involved psychological distress — confusion, hallucinations, panic — talking through it with a trusted person can help. Persistent anxiety, paranoia, or perceptual disturbances lasting more than 24 hours warrant professional evaluation.
Recovery & Support
Synthetic cannabinoid dependence is a recognized clinical condition. Withdrawal may include irritability, sleep disruption, appetite suppression, and anxiety. The prolonged urinary elimination of AB-FUBINACA complicates monitoring — a positive urine test may reflect past heavy use rather than relapse.[16]
Professional support includes addiction medicine specialists, cognitive behavioral therapy, and peer support groups. SAMHSA's National Helpline (1-800-662-4357) provides free referrals in the United States.
Recovery resources, crisis lines, and support pathways → View all
Emergency Response
Recognizing an emergency: Unresponsiveness, seizure, chest pain, breathing difficulty, blue-tinged lips or fingers, extreme agitation with self-harm risk, or collapse. These distinguish a medical emergency from an uncomfortable but self-resolving experience.
- 1. Call emergency services immediately if any of the above signs appear.
- 2. Place an unconscious but breathing person in the recovery position (on their side, airway clear).
- 3. Do not leave the person alone. Monitor breathing continuously.
- 4. Do not restrain an agitated person unless they are in immediate physical danger — restraint can worsen cardiovascular stress.
- 5. If the person stops breathing, begin CPR if trained.
What to tell the dispatcher: The substance taken (synthetic cannabinoid or AB-FUBINACA if known), approximate amount and time, current symptoms, and whether other substances were involved. Good Samaritan laws in many jurisdictions protect people who call for help during a drug emergency.
No specific reversal agent for synthetic cannabinoid intoxication exists. Treatment is supportive.
Legal Status[edit]
AB-FUBINACA is controlled in most major jurisdictions — one of the first synthetic cannabinoids of its class to be specifically scheduled, beginning with Japan in December 2012.[3] It was added to Schedule II of the 1971 UN Convention on Psychotropic Substances in 2020,[10] obligating signatory nations to implement controls.
| Jurisdiction | Classification | Key provisions |
|---|---|---|
| United States | Schedule I (Controlled Substances Act) | Temporary scheduling January 2014; permanent placement September 6, 2016 (81 FR 61498)[2] |
| United Kingdom | Class B (Misuse of Drugs Act 1971) | Controlled under third-generation SCRA generic definition, effective December 14, 2016citation needed |
| Germany | Anlage II (Narcotics Act) | Scheduled November 2014citation needed |
| Japan | Designated Substance (Pharmaceutical and Medical Device Act) | First jurisdiction to schedule; December 2012[3] |
| China | Controlled substance | Effective October 2015citation needed |
| Finland | Banned (government decree on psychoactive substances) | Effective October 19, 2017citation needed |
| International (UN) | Schedule II, 1971 Convention on Psychotropic Substances | Placed 2020[10] |
| Canada | Not specifically confirmed | May be captured under CDSA analog provisions; status unverifiedcitation needed |
| Australia | Not specifically confirmed | May be captured under analog provisions of the SUSMP; status unverifiedcitation needed |
Its scheduling contributed to market displacement toward newer, unscheduled synthetic cannabinoid analogs — a pattern that repeats with every ban.
Legal status changes frequently and varies by jurisdiction. The information above reflects the best available data but may be out of date. This article does not constitute legal advice.
references
- [1]
- [2]
- [3] ^abcdUchiyama N, Matsuda S, Wakana D, Kikura-Hanajiri R, Goda Y (2012) New cannabimimetic indazole derivatives, N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-pentyl-1H-indazole-3-carboxamide (AB-PINACA) and N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide (AB-FUBINACA) identified as designer drugs in illegal products — Forensic Toxicology doi:10.1007/s11419-012-0171-4
- [4] ^abcdShopan N, Scolnik D, Hassoun E, Firsow A, Volkov I, Glatstein M (2023) Acute intoxication caused by three common synthetic cannabinoids: The experience of a large, urban, tertiary care hospital — American Journal of Emergency Medicine doi:10.1016/j.ajem.2023.08.007
- [5] ^abcdTrexler KR, Vanegas SO, Poklis JL, Kinsey SG (2020) The short-acting synthetic cannabinoid AB-FUBINACA induces physical dependence in mice — Drug and Alcohol Dependence doi:10.1016/j.drugalcdep.2020.108179
- [6] ^abcdeLam RPK, Tang MHY, Leung SC, Chong YK, Tsui MSH, Mak TWL (2017) Supraventricular tachycardia and acute confusion following ingestion of e-cigarette fluid containing AB-FUBINACA and ADB-FUBINACA: a case report with quantitative analysis of serum drug concentrations — Clinical Toxicology doi:10.1080/15563650.2017.1307385