generation run 2026-05-09
69 min completedmodel pipeline-v5plan not recordedrun/76c675c7…Selection
Verification
- record
- seen / partial
- working
The model's own caveats
- sparse_evidence
- follow_up_needed
Reproduce
- inputs
- 38 source keys (listed under Sources)
- plan
- not recorded — template version, prompt hash and git SHA are written from 2026-09 onward
- model
- pipeline-v5
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- none — agent transcripts are persisted from 2026-09 onward
21 searches — query, source, results, what was kept and why
| # | source | query | seen | kept | rationale |
|---|---|---|---|---|---|
| 1 | PubMed · absence | hydrocodone pharmacokinetics bioavailability half-life metabolism CYP | 0 | — | — |
| 2 | PubMed | hydrocodone metabolism CYP2D6 norhydrocodone hydromorphone | 5 | 5 | Core pharmacokinetic and metabolic pathway data for hydrocodone |
| 3 | PubMed | PMID 14998425 | 1 | 1 | Core metabolism study |
| 4 | PubMed · absence | hydrocodone opioid receptor binding affinity Ki mu kappa | 0 | — | — |
| 5 | OpenAlex | hydrocodone pharmacology opioid (sort: citations) | 10 | 5 | Highly cited papers directly relevant to hydrocodone prescribing, metabolism, and epidemiology |
| 6 | PubMed | hydrocodone opioid receptor binding Ki affinity mu receptor | 2 | 2 | Primary receptor binding affinity data for hydrocodone |
| 7 | PubMed | hydrocodone clinical pharmacology analgesic | 10 | 3 | Directly relevant to hydrocodone CYP2D6 metabolism and clinical outcomes |
| 8 | PubChem | hydrocodone | 1 | 1 | Primary chemical identity verification |
| 9 | PubMed | PMID 26350273 | 1 | 1 | Key CYP pathway characterization |
| 10 | PubMed | hydrocodone oral bioavailability pharmacokinetics Tmax plasma concentration | 1 | 1 | Key PK paper for ER hydrocodone with food and alcohol interactions |
| 11 | WebSearch | hydrocodone rescheduled Schedule II DEA 2014 Hydrocodone Combination Products | 10 | 3 | Legal scheduling history |
| 12 | PubMed | hydrocodone rescheduling impact prescribing patterns outcomes 2014 | 2 | 2 | Real-world impact of rescheduling on prescribing patterns |
| 13 | WebSearch | hydrocodone history synthesis 1920 Carl Mannich Germany first synthesis | 10 | 2 | Historical synthesis data not available in PubMed |
| 14 | WebSearch | hydrocodone SMILES InChI CAS number 125-29-1 molecular properties PubChem | 10 | 2 | Chemical identity data including SMILES |
| 15 | OpenAlex | hydrocodone single entity extended release Zohydro pharmacokinetics (citations sort) | 8 | 3 | Key ER hydrocodone PK and policy impact data |
| 16 | WebSearch | hydrocodone legal status UK controlled drug schedule Canada Australia international | 10 | 1 | Legal status research for jurisdictions outside US |
| 17 | PubMed | hydrocodone acetaminophen combination side effects clinical trial pain | 6 | 3 | Clinical trial data on hydrocodone/acetaminophen combination efficacy and safety |
| 18 | ClinicalTrials.gov | hydrocodone pain analgesia | 10 | 2 | Clinical trials directly evaluating hydrocodone for pain |
| 19 | PubMed | PMID 31454279 | 1 | 1 | Key rescheduling impact study |
| 20 | WebSearch | hydrocodone equianalgesic morphine milligram equivalent 1:1 ratio CDC conversion | 10 | 2 | Equianalgesic dosing data |
| 21 | WebSearch | GHB GBL opioid combination fatal respiratory depression pharmacodynamic interaction | 10 | 2 | Mechanism of lethal GHB/opioid interaction |
67 claims by section — every cited sentence, checked against its source
safety17 · 12 ok
Claim in safety — inconclusiveinconclusiveworking →
Autopsy findings in opioid-related deaths characteristically include pulmonary edema and congestion with frothy watery fluid in the airwayssupported
Pulmonary edema/congestion are key autopsy findings. 2017.003
Opioid use disorder caused 53,774 U.S. deaths in 2024 and affected 3.7% of adultssupported
Opioid use disorder affected ~3.7% of US adults (9.4M) in 2022 and caused 53,774 deaths in 2024. jama.2025.26348
Paulozzi et al. established that opioid analgesic poisoning deaths — driven substantially by hydrocodone prescribing — exceeded heroin and cocaine deaths combined by 2002partially supported
Opioid analgesic poisoning listed in 5528 deaths in 2002 - more than heroin or cocaine. pds.1276
Opioids subsequently became responsible for more deaths than suicide and motor vehicle crashes.supported
Opioid analgesics now responsible for more deaths than both suicide/motor vehicle crashes or cocaine/heroin combined. es9
Evidence-based treatment for opioid use disorder includes buprenorphine-naloxone (partial agonist substitution therapy), methadone (full agonist substitution), and naltrexone (antagonist-based relapse prevention).supported
Reviews medications for OUD, withdrawal, and overdose reversal. jama.2025.26348
Farrar et al. found that only approximately 44.5% of chronic non-cancer pain patients maintained pain level and opioid dose stability over 12 months on extended-release opioids, reflecting the clinical reality of tolerance development.supported
Patient-level analysis of FDA data from 3,192 patients on ER oxycodone/hydrocodone: ~44.5% maintained pain and opioid dose stability at 12 months. j.pain.0000000000002331
The hydrocodone-alcohol interaction operates through dual mechanisms: pharmacodynamic (additive CNS and respiratory depression) and pharmacokinetic (40% ethanol increases hydrocodone ER Cmax by approximately 135% and shortens Tmax from 6.16 to 2.43 hours)supported
40% alcohol increased AUC by 20% and Cmax from 46.3 to 109 ng/mL, shortened tmax to 2.43 h. cpaa.s70831
Claim in safety — not_supportednot supportedworking →
Fields et al. found that alprazolam and diazepam co-ingestion significantly decreased hydrocodone blood concentrations in postmortem cases — likely through CYP3A4 competition — while deaths still occurred, indicating synergistic CNS toxicity at lower drug concentrations than would be expected for either drug alonesupported
Alprazolam + diazepam significantly decreased median hydrocodone concentrations by 48% but deaths still occurred at lower concentrations, suggesting synergistic toxicity. 1556-4029.12807
Claim in safety — inconclusiveinconclusiveworking →
Claim in safety — inconclusiveinconclusiveworking →
Claim in safety — inconclusiveinconclusiveworking →
CYP2D6 ultra-rapid metabolizer status — excessive hydromorphone formation may produce disproportionate opioid effects at standard dosessupported
CYP2D6 variability is a major cause of opioid efficacy and safety differences. Applicable to other CYP2D6-metabolized opioids including hydrocodone. clpt.2013.254
Pregnancy — neonatal opioid withdrawal syndrome (NOWS) is documented with in-utero opioid exposure; maternal pharmacokinetic data during pregnancy are limitedsupported
Hydrocodone, oxycodone, and codeine are the most prescribed opioids but have major pharmacology knowledge gaps in maternal and pediatric populations. phar.70024
Concurrent benzodiazepine or CNS depressant use — synergistic respiratory depression; substantially elevated overdose mortality risksupported
Alprazolam + diazepam significantly decreased median hydrocodone concentrations by 48% but deaths still occurred at lower concentrations, suggesting synergistic toxicity. 1556-4029.12807
Concurrent benzodiazepine or CNS depressant use — synergistic respiratory depression; substantially elevated overdose mortality risksupported
Benzodiazepines when combined with opioids produce significant respiratory depression. 0897190013515001
pharmacology13 · 10 ok
A pharmacologically critical distinction defines hydrocodone's mechanism: the parent compound has moderate MOR affinity (Ki = 19.8 nM), but CYP2D6-mediated O-demethylation yields hydromorphone (Ki ≈ 0.6 nM), approximately 33-fold more potent at MORsupported
Hydrocodone Ki = 19.8 nM at mu receptor (rat brain homogenates with 3H-DAMGO). Hydromorphone Ki = 0.6 nM. Many opioids may exert their pharmacological actions predominantly through metabolites. pmid:1851921
Hosseinnejad et al. demonstrated in a postcesarean cohort that plasma hydromorphone concentration — not plasma hydrocodone — was predictive of pain relief, directly establishing the metabolite as a principal mediator of analgesic efficacy.supported
plasma hydromorphone, not hydrocodone, was predictive of pain relief. jalm.2018.026070
Hydrocodone undergoes extensive hepatic first-pass metabolism via two primary CYP-mediated pathways:supported
To determine the Michaelis-Menten kinetics of hydrocodone metabolism to its O- and N-demethylated products, hydromorphone and norhydrocodone, to determine the individual cytochrome p450 enzymes involved. pmid:14998425
Hydrocodone undergoes extensive hepatic first-pass metabolism via two primary CYP-mediated pathways:supported
Hydrocodone undergoes cytochrome P-450 (CYP)-mediated metabolism involving the CYP3A4 and CYP2D6 isozymes. j.clinthera.2015.08.007
Hydrocodone undergoes extensive hepatic first-pass metabolism via two primary CYP-mediated pathways:supported
Hydrocodone is metabolized by cytochrome P450 (CYP) 2D6 into hydromorphone and by CYP3A4 into norhydrocodone. bku051
CYP3A4 (N-demethylation) → norhydrocodone — the major metabolic pathway by mass. Norhydrocodone is considered pharmacologically inactive or weakly active. Mean urinary norhydrocodone mole fraction: approximately 49% of total metabolite outputsupported
Mean hydrocodone, hydromorphone and norhydrocodone mole fractions were 0.39, 0.12 and 0.49, respectively. bku051
CYP2D6 (O-demethylation) → hydromorphone — a minor pathway by mass (approximately 12% of urinary drug and metabolites) but pharmacologically significant due to hydromorphone's 33-fold greater MOR affinitysupported
Mean hydrocodone, hydromorphone and norhydrocodone mole fractions were 0.39, 0.12 and 0.49, respectively. bku051
Claim in pharmacology — inconclusiveinconclusiveworking →
Poor metabolizers exhibit substantially reduced hydromorphone formation and correspondingly reduced analgesiasupported
Individuals with absent (poor metabolizers) or reduced (intermediate metabolizers) CYP2D6 enzyme activity have lower concentrations of highly potent active metabolites of tramadol, hydrocodone, and codeine. jamanetworkopen.2025.58299
Poor metabolizers exhibit substantially reduced hydromorphone formation and correspondingly reduced analgesiasupported
CYP2D6 bioactivates hydrocodone, tramadol, codeine, and oxycodone to active metabolites providing analgesic activity. Reduced CYP2D6 activity may be associated with poor pain control. jamanetworkopen.2025.23543
Claim in pharmacology — inconclusiveinconclusiveworking →
CYP3A4 and CYP3A5 genotype does not significantly predict pain relief from hydrocodone.supported
CYP2D6 is responsible for metabolizing hydrocodone; rate of hydromorphone formation was dependent on the genotype of CYP2D6 and plasma hydromorphone, not hydrocodone, was predictive of pain relief. jalm.2018.026070
Claim in pharmacology — inconclusiveinconclusiveworking →
pharmacokinetic-detail9 · 7 ok
Hydrocodone metabolism is dominated by two CYP-mediated oxidative pathways characterized in human liver microsomes:supported
To determine the Michaelis-Menten kinetics of hydrocodone metabolism to its O- and N-demethylated products, hydromorphone and norhydrocodone, to determine the individual cytochrome p450 enzymes involved. pmid:14998425
CYP3A4: N-demethylation → norhydrocodone — the quantitatively major pathway. Norhydrocodone accounts for approximately 49% of total urinary drug and metabolites in a large-scale clinical sample (n = 76,924 specimens). Norhydrocodone is considered pharmacologically inactive or weakly active at MOR.supported
Mean hydrocodone, hydromorphone and norhydrocodone mole fractions were 0.39, 0.12 and 0.49, respectively. bku051
CYP2D6: O-demethylation → hydromorphone — the quantitatively minor but pharmacologically dominant pathway. Hydromorphone accounts for approximately 12% of urinary drug and metabolites but possesses 33-fold greater MOR affinity than the parent compound.supported
Mean hydrocodone, hydromorphone and norhydrocodone mole fractions were 0.39, 0.12 and 0.49, respectively. bku051
Parent hydrocodone accounts for approximately 39% of total urinary output.supported
Mean hydrocodone, hydromorphone and norhydrocodone mole fractions were 0.39, 0.12 and 0.49, respectively. bku051
Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →
Poor metabolizers exhibit substantially reduced hydromorphone formation, resulting in diminished analgesia and increased risk of inadequate pain control.supported
Individuals with absent (poor metabolizers) or reduced (intermediate metabolizers) CYP2D6 enzyme activity have lower concentrations of highly potent active metabolites of tramadol, hydrocodone, and codeine. jamanetworkopen.2025.58299
Poor metabolizers exhibit substantially reduced hydromorphone formation, resulting in diminished analgesia and increased risk of inadequate pain control.supported
CYP2D6 bioactivates hydrocodone, tramadol, codeine, and oxycodone to active metabolites providing analgesic activity. Reduced CYP2D6 activity may be associated with poor pain control. jamanetworkopen.2025.23543
Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →
CYP3A4 and CYP3A5 genotype does not significantly predict pain relief from hydrocodone.supported
CYP2D6 is responsible for metabolizing hydrocodone; rate of hydromorphone formation was dependent on the genotype of CYP2D6 and plasma hydromorphone, not hydrocodone, was predictive of pain relief. jalm.2018.026070
history8 · 8 ok
Phase 3 trials of suzetrigine (VX-548), a novel NaV1.8 inhibitor, used hydrocodone bitartrate 5 mg/acetaminophen 300 mg as the reference arm in bunionectomy and abdominoplasty pain, with VX-548 demonstrating non-inferior efficacysupported
Phase 3 trials comparing VX-548 (suzetrigine) vs. hydrocodone bitartrate/acetaminophen and placebo in bunionectomy and abdominoplasty pain. VX-548 significantly reduced pain vs. placebo; non-inferior to hydrocodone/APAP. aln.0000000000005460
By 2011, HCPs had become the most-prescribed drug class in the United States, with 136.7 million prescriptions dispensed annuallysupported
Hydrocodone topped all prescriptions with 136.7 million prescriptions in 2011. es9
The United States accounted for approximately 99% of global hydrocodone consumption.supported
US consumes ~99% of world's hydrocodone supply. 2332-2780-1600078
Paulozzi et al. established in 2006 that opioid analgesic poisoning deaths had exceeded heroin and cocaine deaths combined by 2002partially supported
Opioid analgesic poisoning listed in 5528 deaths in 2002 - more than heroin or cocaine. pds.1276
Opioids subsequently became responsible for more deaths than suicide and motor vehicle crashessupported
Opioid analgesics now responsible for more deaths than both suicide/motor vehicle crashes or cocaine/heroin combined. es9
Shen et al. documented HCP use declining from 55% to 40% among older breast cancer patients, with compensatory prescribing shifts to other opioidssupported
Hydrocodone use declined from 55% to 40% after rescheduling; non-hydrocodone opioid use increased from 43% to 50%. curroncol32110593
Yan et al. recorded significant reductions in dental hydrocodone prescribingsupported
Dentists frequently prescribe hydrocodone. 2014 DEA rescheduling to Schedule II introduced restricted prescribing; changed dental prescribing of opioids. 23800844221102830
Cavallari et al. demonstrated in a randomized trial that CYP2D6-guided opioid management improves postoperative pain control, and Nahid et al. linked CYP2D6 phenotype to emergency department utilization among opioid-treated patientssupported
Individuals with absent (poor metabolizers) or reduced (intermediate metabolizers) CYP2D6 enzyme activity have lower concentrations of highly potent active metabolites of tramadol, hydrocodone, and codeine. jamanetworkopen.2025.58299
clinical-evidence6 · 6 ok
Bertoch et al. conducted two Phase 3 randomized clinical trials comparing suzetrigine, a novel NaV1.8 inhibitor, against hydrocodone bitartrate 5 mg/acetaminophen 300 mg as the active comparator in bunionectomy and abdominoplasty painsupported
Phase 3 trials comparing VX-548 (suzetrigine) vs. hydrocodone bitartrate/acetaminophen and placebo in bunionectomy and abdominoplasty pain. aln.0000000000005460
Cooper et al. conducted a randomized, double-blind, placebo-controlled trial comparing analgesic efficacy of naproxen sodium versus hydrocodone/acetaminophen in acute postsurgical dental painsupported
Compared single dose naproxen sodium 440 mg against hydrocodone plus acetaminophen 10/650 mg in post-impaction surgery pain. 00325481.2021.2008180
Chumpitazi et al. evaluated hydrocodone/acetaminophen for pediatric laceration repair in a randomized trial, extending the evidence base for hydrocodone use in pediatric populations.supported
Measured effect of hydrocodone/acetaminophen elixir in reducing pain and anxiety in children undergoing sutured laceration repair in the emergency department. prs.0000000000006383
Farrar et al. conducted a harmonization analysis of FDA patient-level data from abuse-deterrent oxycodone and hydrocodone studies, finding that only approximately 44.5% of 3,192 chronic non-cancer pain patients maintained pain level and opioid dose stability over 12 monthssupported
Patient-level analysis of FDA data from 3,192 patients on ER oxycodone/hydrocodone: ~44.5% maintained pain and opioid dose stability at 12 months. j.pain.0000000000002331
This finding challenges the premise of long-term opioid efficacy maintenance and is consistent with the broader Cochrane assessment by Noble et al. that long-term opioid therapy for chronic non-cancer pain produces sustained benefit in only a minority of patients.supported
Cochrane review (26 studies, 4,893 participants). Many patients discontinue long-term opioids due to adverse events (22.9% oral) or insufficient pain relief (10.3%). 14651858.cd006605.pub2
Cavallari et al. conducted a randomized clinical trial of CYP2D6-guided opioid management in postoperative pain controlsupported
Individuals with absent (poor metabolizers) or reduced (intermediate metabolizers) CYP2D6 enzyme activity have lower concentrations of highly potent active metabolites of tramadol, hydrocodone, and codeine. jamanetworkopen.2025.58299
comparative-pharmacology5 · 5 ok
At the receptor level, hydrocodone's MOR Ki of 19.8 nM ranks it below hydromorphone (0.6 nM), fentanyl, and buprenorphine, but above codeine and tramadol (both > 100 nM).supported
Experiments were conducted to obtain Ki values for 19 approved opioid drugs using a single binding assay in a cell membrane preparation expressing recombinant human MOR. Hydrocodone falls in the Ki=1-100 nM range. j.yrtph.2010.12.007
At the receptor level, hydrocodone's MOR Ki of 19.8 nM ranks it below hydromorphone (0.6 nM), fentanyl, and buprenorphine, but above codeine and tramadol (both > 100 nM).supported
Hydrocodone Ki = 19.8 nM at mu receptor (rat brain homogenates with 3H-DAMGO). Hydromorphone Ki = 0.6 nM. pmid:1851921
The critical difference is magnitude: codeine has negligible intrinsic MOR activity (Ki > 100 nM) and functions almost entirely as a prodrug for morphine, whereas hydrocodone retains moderate MOR affinity (Ki = 19.8 nM) and produces pharmacological effects even in CYP2D6 poor metabolizers — though with reduced analgesic efficacy.supported
Individuals with absent (poor metabolizers) or reduced (intermediate metabolizers) CYP2D6 enzyme activity have lower concentrations of highly potent active metabolites of tramadol, hydrocodone, and codeine. jamanetworkopen.2025.58299
Murphy et al. compared rates of mortality and serious adverse effects among commonly prescribed opioid analgesicssupported
Epidemic of prescription opioid overdose and mortality parallels dispensing rates; evaluation of comparative mortality rates among commonly prescribed opioids including hydrocodone. s40264-018-0660-4
Piper et al. documented trends in medical opioid use from 2006–2016, capturing the peak and decline of hydrocodone prescribing.supported
Nationwide examination of opioid distribution patterns 2006-2016. j.amepre.2018.01.034
summary5 · 5 ok
The United States accounts for approximately 99% of global consumptionsupported
US consumes ~99% of world's hydrocodone supply. 2332-2780-1600078
Hydrocodone ((4R,4aR,7aR,12bS)-9-methoxy-3-methyl-1,2,4,4a,5,6,7a,13-octahydro-4,12-methanobenzofuro[3,2-e]isoquinolin-7-one) is a semi-synthetic morphinan opioid and full μ-opioid receptor (MOR) agonist with moderate receptor affinity (Ki = 19.8 nM)supported
Hydrocodone Ki = 19.8 nM at mu receptor (rat brain homogenates with 3H-DAMGO). pmid:1851921
FDA in 1943, hydrocodone became the most-prescribed drug in the United States by 2011, with 136.7 million annual prescriptionssupported
Hydrocodone topped all prescriptions with 136.7 million prescriptions in 2011. es9
Hydrocodone activates MOR with a Ki of 19.8 nM in rat brain homogenates, placing it in the moderate-affinity range alongside oxycodone and methadonepartially supported
Experiments were conducted to obtain Ki values for 19 approved opioid drugs using a single binding assay in a cell membrane preparation expressing recombinant human MOR. Hydrocodone falls in the Ki=1-100 nM range. j.yrtph.2010.12.007
Clinical pharmacogenomics data confirm that plasma hydromorphone — not plasma hydrocodone — predicts analgesic efficacy, establishing the metabolite as a principal mediator of therapeutic effect.supported
plasma hydromorphone, not hydrocodone, was predictive of pain relief. jalm.2018.026070
receptor-pharmacology3 · 3 ok
Chen et al. established a Ki of 19.8 nM using rat brain homogenates with ³H-DAMGO as the radioligandsupported
Hydrocodone Ki = 19.8 nM at mu receptor (rat brain homogenates with 3H-DAMGO). pmid:1851921
Volpe et al. confirmed this positioning using recombinant human MOR, placing hydrocodone in the Ki = 1–100 nM range — alongside oxycodone, methadone, and fentanyl — rather than among the high-affinity opioids (hydromorphone, buprenorphine, sufentanil; Ki < 1 nM) or the low-affinity agents (codeine, tramadol; Ki > 100 nM).supported
Experiments were conducted to obtain Ki values for 19 approved opioid drugs using a single binding assay in a cell membrane preparation expressing recombinant human MOR. Hydrocodone falls in the Ki=1-100 nM range. j.yrtph.2010.12.007
Hydromorphone, produced via CYP2D6-mediated O-demethylation, has a MOR Ki of approximately 0.6 nM — 33-fold greater affinity than the parent compoundsupported
Hydrocodone Ki = 19.8 nM at mu receptor (rat brain homogenates with 3H-DAMGO). Hydromorphone Ki = 0.6 nM. pmid:1851921
chemistry1 · 1 ok
The methoxy group at C-3 is the defining structural distinction between hydrocodone and hydromorphone: O-demethylation by CYP2D6 removes this methyl ether, yielding the free phenol of hydromorphone and dramatically increasing MOR affinity from 19.8 nM to approximately 0.6 nMsupported
Hydrocodone Ki = 19.8 nM at mu receptor... Hydromorphone Ki = 0.6 nM. Many opioids may exert their pharmacological actions predominantly through metabolites. pmid:1851921