generation run 2026-05-09
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27 searches — query, source, results, what was kept and why
| # | source | query | seen | kept | rationale |
|---|---|---|---|---|---|
| 1 | ClinicalTrials.gov | tapentadol pain | 10 | 5 | Key regulatory trials; noted Grünenthal as original developer |
| 2 | PubMed | tapentadol overdose toxicity death case report | 2 | 2 | Both directly relevant as documented fatality cases with concentration data |
| 3 | PubMed | tapentadol Tzschentke analgesic preclinical animal model | 7 | 6 | Tzschentke group produced the foundational preclinical pharmacology for tapentadol |
| 4 | PubMed | tapentadol scheduling DEA controlled substance legal status | 1 | 1 | Definitive US scheduling documentation |
| 5 | PubChem | tapentadol | 1 | 1 | Full chemical identity data confirming and supplementing brief seed data |
| 6 | PubMed | tapentadol receptor affinity opioid serotonin norepinephrine in vitro | 1 | 1 | Key paper on transporter selectivity relevant to serotonin syndrome risk |
| 7 | PubMed | tapentadol pharmacology mechanism action mu-opioid norepinephrine | 12 | 7 | All selected as directly relevant to tapentadol pharmacology, mechanism, and safety |
| 8 | PubMed | tapentadol human clinical study acute pain bunionectomy efficacy | 7 | 5 | These constitute the major Phase III acute pain evidence base for FDA approval |
| 9 | PubMed | tapentadol drug-drug interaction pharmacokinetic | 8 | 3 | Establish tapentadol's DDI profile and metabolism pathway |
| 10 | PubMed | tapentadol serotonin syndrome SERT inhibition MAO interaction | 1 | 1 | Key paper linking tapentadol to serotonin syndrome risk mechanisms |
| 11 | PubMed | tapentadol pharmacokinetics bioavailability metabolism human | 8 | 4 | Selected human PK studies; dog study noted as animal data |
| 12 | PubMed | tapentadol abuse dependence misuse addiction potential | 3 | 2 | Selected tapentadol-specific abuse/dependence studies |
| 13 | PubMed | tapentadol FDA approval 2008 chronic pain extended release | 3 | 2 | Reviews confirming approval dates and clinical profile |
| 14 | Web | tapentadol Australia Canada scheduling controlled drug | 10 | 2 | Key jurisdiction scheduling data |
| 15 | PubMed | tapentadol pediatric children safety pharmacokinetics | 3 | 2 | Pediatric safety data |
| 16 | PubMed | tapentadol network meta-analysis opioid safety chronic pain | 6 | 1 | Highest-level evidence for safety comparison |
| 17 | Web | tapentadol UK scheduling Misuse of Drugs Act Class A controlled drug | 10 | 1 | UK legal scheduling status |
| 18 | PubMed | tapentadol cancer pain systematic review efficacy | 8 | 2 | Cancer pain evidence and Cochrane evidence |
| 19 | Web | tapentadol Tzschentke 2007 Journal Pharmacology Experimental Therapeutics binding affinity Ki MOR NET | 10 | 1 | Landmark primary pharmacology paper establishing tapentadol mechanism |
| 20 | PubMed | tapentadol postmarketing surveillance abuse diversion data | 5 | 3 | Post-marketing abuse liability data |
| 21 | PubMed | PMID 17656655 | 1 | 1 | Core primary pharmacology characterization paper |
| 22 | PubMed · absence | tapentadol Tzschentke 2007 binding affinity pharmacological profile | 0 | 0 | Found via web search instead |
| 23 | PubMed | tapentadol constipation gastrointestinal effects comparison oxycodone morphine | 6 | 3 | Key tolerability comparison data |
| 24 | PubMed | tapentadol serotonin syndrome SERT inhibition MAO interaction | 1 | 1 | Case report evidence for serotonin syndrome risk |
| 25 | PubMed | tapentadol withdrawal syndrome discontinuation opioid | 2 | 2 | Withdrawal and tapering evidence |
| 26 | PubChem API | CID 9838022 SMILES properties | 1 | 1 | Complete chemical identity data |
| 27 | Web | tapentadol EU EMA Palexia approval scheduling | 10 | 1 | EU regulatory status |
114 claims by section — every cited sentence, checked against its source
safety37 · 21 ok
The primary mechanism of acute lethality is respiratory depression and CNS depression via MOR agonismsupported
Cause of death narcotic intoxication. Possible mechanisms: respiratory depression, CNS depression, serotonin syndrome. paf.0b013e3182887804
Claim in safety — inconclusiveinconclusiveworking →
The first reported tapentadol death involved a 34-year-old male who apparently injected the drug intravenously. Postmortem femoral blood concentration was 1.05 mg/L; heart blood was 3.20 mg/L. No other substances were detected beyond nicotine/cotinine.supported
34-year-old male first reported tapentadol death. Femoral blood 1.05 mg/L, heart blood 3.20 mg/L. j.1556-4029.2012.02299.x
A female fatality with peripheral blood concentration 1.1 mg/L, central blood 1.3 mg/L, liver 9.9 mg/kg, and vitreous humor 0.94 mg/L. Co-intoxication with oxycodone (0.58 mg/L) was present; manner of death was determined as suicide.supported
Peripheral blood TAP 1.1 mg/L, central blood 1.3 mg/L, liver 9.9 mg/kg, vitreous 0.94 mg/L. Mixed oxycodone (0.58 mg/L) and tapentadol intoxication, suicide. j.forsciint.2016.08.020
A case with heart blood concentration exceeding 20× the therapeutic range. Cause of death was narcotic intoxication; possible contributing mechanisms cited included respiratory depression, CNS depression, and serotonin syndrome.supported
Heart blood tapentadol >20x upper therapeutic range. Cause of death narcotic intoxication. Possible mechanisms: respiratory depression, CNS depression, serotonin syndrome. paf.0b013e3182887804
Claim in safety — not_supportednot supportedworking →
Claim in safety — not_supportednot supportedworking →
Severe hepatic impairment increases bioavailability due to reduced first-pass glucuronidationsupported
Tapentadol is glucuronidated by UGT1A9 and UGT2B7. Co-administration with sorafenib (UGT inhibitor) increased tapentadol Cmax 5.3-fold. j.biopha.2020.110530
Dependence-related psychological effects: Drug-seeking behavior, preoccupation with supply, and dose escalation may develop with chronic use, though post-marketing surveillance indicates these occur at lower rates than with comparator Schedule II opioids.supported
Tapentadol abuse event rates significantly lower than all other opioids per population-level denominators. j.jpain.2017.11.007
Tolerance to tapentadol's analgesic effects develops with chronic administration but at approximately half the rate of morphine tolerance in the CCI neuropathic pain modelsupported
Tolerance development twice as slow as morphine. pmid:17656655
After 31 days of administration in rodents, tapentadol tolerance is comparable in magnitude to tramadol tolerance and markedly less than morphine tolerance.supported
Chronic tapentadol resulted in tolerance similar to tramadol but much less than morphine. j.ejphar.2021.174245
The nitric oxide synthase system modulates tolerance development: NOS inhibition with L-NOArg reverses established tapentadol tolerance and attenuates naloxone-precipitated withdrawal in rodentssupported
NOS inhibitor L-NOArg reversed tapentadol tolerance. Tapentadol decreased nNOS in dorsal root ganglia. j.ejphar.2021.174245
Optimal tapering strategy is recommended for discontinuation.supported
Overview of opioid therapy discontinuation; optimal tapering of tapentadol in chronic non-cancer pain. 03007995.2022.2148459
US post-marketing surveillance using the RADARS system demonstrated that tapentadol abuse event rates per population-level denominators were significantly lower than all other opioids examined, including tramadol, hydrocodone, morphine, oxycodone, hydromorphone, and oxymorphonesupported
RADARS system retrospective cohort 2011-2016. Tapentadol abuse event rates significantly lower than all other opioids per population-level denominators. j.jpain.2017.11.007
Treatment-seeking surveillance (ASI-MV) confirmed consistently low levels of abuse and diversion for the ER formulation.supported
Postmarketing surveillance of tapentadol ER using ASI-MV. Consistently low levels of abuse and diversion. pnz250
Animal CPP studies show that tapentadol induces short-term place preference but does not retain this preference at 7 or 14 days, suggesting lower rewarding memory formation and craving incubation than tramadol.supported
Both induce short-term CPP. Only tramadol retains CPP at 7/14 days. Tapentadol does not cause CPP retention despite higher CNS activity. ph16010086
Australian post-marketing surveillance documented extra-medical use, with monitoring ongoingsupported
Post-marketing surveillance of tapentadol SRF in Australia (marketed Feb 2013). Examines extra-medical use, attractiveness for extra-medical use, and associated harms. j.drugalcdep.2019.107697
International analysis identified under-reporting of abuse in Southeast Asian countries.supported
Evaluates tapentadol abuse cases using real-world data; identifies under-reporting in Southeast Asian Region. 03007995.2024.2427881
Claim in safety — inconclusiveinconclusiveworking →
Claim in safety — inconclusiveinconclusiveworking →
Claim in safety — not_supportednot supportedworking →
Claim in safety — inconclusiveinconclusiveworking →
Combination with SSRIs, SNRIs, tricyclic antidepressants, linezolid, or methylene blue increases serotonin syndrome risksupported
SERT inhibition may contribute to serotonin syndrome risk, particularly with MAOIs or SSRIs. bph.14105
Combination with SSRIs, SNRIs, tricyclic antidepressants, linezolid, or methylene blue increases serotonin syndrome risksupported
SERT inhibition may contribute to serotonin syndrome risk with MAOIs, SSRIs, SNRIs, TCAs. s00204-018-2244-6
Claim in safety — not_supportednot supportedworking →
Post-marketing surveillance has not confirmed the serotonin syndrome signal at standard doses, but case reports document serotonin syndrome in overdose contexts.supported
Case report of probable tapentadol-induced serotonin syndrome after overdose. Only second published case of suspected tapentadol serotonin syndrome. hpj5104-320
Sorafenib co-administration increased Cmax 5.3-fold and AUC 1.5-fold in an animal modelpartially supported
Co-administration with sorafenib (UGT inhibitor) increased tapentadol Cmax 5.3-fold. j.biopha.2020.110530
Claim in safety — not_supportednot supportedworking →
Claim in safety — inconclusiveinconclusiveworking →
Claim in safety — inconclusiveinconclusiveworking →
Claim in safety — not_supportednot supportedworking →
Claim in safety — inconclusiveinconclusiveworking →
Claim in safety — not_supportednot supportedworking →
Claim in safety — not_supportednot supportedworking →
Claim in safety — not_supportednot supportedworking →
Concurrent serotonergic drugs: Relative contraindication. SSRIs, SNRIs, and TCAs increase serotonin syndrome risk, particularly at supratherapeutic tapentadol doses.supported
SERT inhibition may contribute to serotonin syndrome risk, particularly with MAOIs or SSRIs. bph.14105
Concurrent serotonergic drugs: Relative contraindication. SSRIs, SNRIs, and TCAs increase serotonin syndrome risk, particularly at supratherapeutic tapentadol doses.supported
Case report of probable tapentadol-induced serotonin syndrome after overdose. hpj5104-320
pharmacology26 · 15 ok
Tapentadol also inhibits the serotonin transporter (SERT) in vitro, but substantially less potently than tramadolsupported
Tapentadol and tramadol inhibit human SERT in HEK293 cells. s00204-018-2244-6
Tapentadol operates through a dual mechanism combining μ-opioid receptor (MOR) agonism and norepinephrine reuptake inhibition (NRI) in a single molecule — a pharmacological profile designated "MOR-NRI" by Tzschentke and colleaguessupported
Tapentadol is a novel, centrally-acting analgesic drug acting as a MOR agonist and noradrenaline reuptake inhibitor. s40263-014-0151-9
This dual action is not simply additive: the two mechanisms produce synergistic analgesia, with the NRI component activating descending noradrenergic pain inhibition pathways that complement the ascending pain suppression mediated by MOR agonism.supported
Despite 50-fold lower MOR affinity, only 2-3x less potent than morphine. pmid:17656655
At the μ-opioid receptor, tapentadol acts as a full agonist with Ki = 0.1 μM in rat brain membrane preparations and relative efficacy of 88% versus morphine in the [³⁵S]GTPγS functional assaysupported
MOR agonist Ki=0.1 microM (88% efficacy vs morphine) pmid:17656655
This affinity is approximately 50-fold lower than morphine (MOR Ki = 0.002 μM), yet tapentadol's in vivo analgesic potency is only 2–3-fold lower than morphine in animal pain models — a disparity that constitutes the primary evidence for synergistic dual-mechanism analgesiasupported
Despite 50-fold lower MOR affinity, only 2-3x less potent than morphine. pmid:17656655
Confirmation of this synergy comes from μ-opioid receptor knockout mice (OPRM1⁻/⁻), in which tapentadol retains partial antinociceptive and antihyperalgesic activity attributable to the NRI component alone.supported
In MOR KO mice, morphine fails but tapentadol retains significant antinociceptive activity abolished by alpha-2 antagonist yohimbine. j.neulet.2011.01.014
The norepinephrine reuptake inhibition component shows Ki = 0.5 μM for synaptosomal norepinephrine reuptake inhibitionsupported
NE reuptake inhibitor Ki=0.5 microM. pmid:17656655
In vivo microdialysis demonstrates that tapentadol at 10 mg/kg IP increases extracellular norepinephrine by +450% in rat brain, whereas equianalgesic morphine produces no significant norepinephrine increasesupported
Microdialysis shows +450% extracellular NE at 10 mg/kg IP. pmid:17656655
Tapentadol also inhibits the serotonin transporter (SERT) in vitro, but substantially less potently than tramadolsupported
also inhibits SERT but less potently than tramadol. bph.14105
Claim in pharmacology — not_supportednot supportedworking →
Isolated case reports of serotonin syndrome exist in overdose contexts.supported
Case report of probable tapentadol-induced serotonin syndrome after overdose. Only second published case of suspected tapentadol serotonin syndrome. hpj5104-320
A comprehensive molecular pharmacology screen by Olson and colleagues identified sigma-1 receptor binding for tapentadol in radioligand binding assays — a novel interaction not previously established for the drugsupported
Tapentadol showed sigma-1 receptor binding in comprehensive opioid receptor screening. journal.pone.0217371
Claim in pharmacology — not_supportednot supportedworking →
Claim in pharmacology — inconclusiveinconclusiveworking →
Claim in pharmacology — not_supportednot supportedworking →
Claim in pharmacology — inconclusiveinconclusiveworking →
Claim in pharmacology — not_supportednot supportedworking →
A critical differentiating feature of tapentadol's metabolism is its primary dependence on Phase II glucuronidation via UGT1A9 and UGT2B7, rather than Phase I CYP450 oxidationsupported
Tapentadol is glucuronidated by UGT1A9 and UGT2B7. j.biopha.2020.110530
A critical differentiating feature of tapentadol's metabolism is its primary dependence on Phase II glucuronidation via UGT1A9 and UGT2B7, rather than Phase I CYP450 oxidationsupported
No CYP metabolism; glucuronidated by UGT. s40265-021-01515-z
This metabolic pathway has two major clinical implications: first, CYP2D6 and CYP3A4 genetic polymorphisms do not meaningfully alter tapentadol pharmacokinetics or analgesic efficacy — a fundamental differentiation from tramadol, which requires CYP2D6 conversion to its active metabolite O-desmethyltramadolsupported
No CYP metabolism; glucuronidated by UGT. s40265-021-01515-z
Claim in pharmacology — inconclusiveinconclusiveworking →
The major metabolite, tapentadol-O-glucuronide, shows negligible activity at MOR and NET, with systemic exposure exceeding 45-fold below Ki values at therapeutic dosessupported
Major metabolite tapentadol-O-glucuronide has no analgesic effects. Systemic exposure to metabolites far below Ki values at MOR/NET (>45-fold). mf.2010.32.1.1434165
Claim in pharmacology — not_supportednot supportedworking →
Claim in pharmacology — inconclusiveinconclusiveworking →
Claim in pharmacology — inconclusiveinconclusiveworking →
Claim in pharmacology — inconclusiveinconclusiveworking →
summary12 · 10 ok
Overdose risk is substantial: respiratory depression and CNS depression via MOR agonism constitute the primary lethal mechanisms, with fatal blood concentrations documented at 1.0–3.2 mg/L in forensic case reportssupported
34-year-old male first reported tapentadol death. Femoral blood 1.05 mg/L, heart blood 3.20 mg/L. Autopsy consistent with opiate-type overdose. j.1556-4029.2012.02299.x
Overdose risk is substantial: respiratory depression and CNS depression via MOR agonism constitute the primary lethal mechanisms, with fatal blood concentrations documented at 1.0–3.2 mg/L in forensic case reportssupported
41-year-old female fatality. Peripheral blood TAP 1.1 mg/L, central blood 1.3 mg/L. j.forsciint.2016.08.020
It operates through a first-in-class dual mechanism combining μ-opioid receptor (MOR) agonism and norepinephrine reuptake inhibition (NRI) within a single molecule — a profile designated "MOR-NRI"supported
Tapentadol is a novel, centrally-acting analgesic drug acting as a MOR agonist and noradrenaline reuptake inhibitor. s40263-014-0151-9
Claim in summary — not_supportednot supportedworking →
Developed by Grünenthal GmbH under the code CG5503, tapentadol was first pharmacologically characterized by Tzschentke and colleagues in 2007supported
(-)-(1R,2R)-3-(3-dimethylamino-1-ethyl-2-methyl-propyl)-phenol hydrochloride (tapentadol HCl): a novel mu-opioid receptor agonist/norepinephrine reuptake inhibitor with broad-spectrum analgesic properties pmid:17656655
Claim in summary — inconclusiveinconclusiveworking →
The US FDA approved the immediate-release formulation in November 2008 — the first new centrally acting analgesic class approved in 25 years — followed by an extended-release formulation in 2011supported
FDA approved November 2008 for acute pain, August 2011 for chronic pain ER. j.pharep.2018.01.005
Tapentadol binds the μ-opioid receptor with Ki = 0.1 μM in rat brain membranes (50-fold lower affinity than morphine) yet produces analgesic potency only 2–3-fold below morphine, a disparity attributable to synergistic NRI-mediated descending pain inhibitionsupported
MOR agonist Ki=0.1 microM. Despite 50-fold lower MOR affinity, only 2-3x less potent than morphine. pmid:17656655
Tapentadol forms no clinically relevant active metabolites and is metabolized primarily via UGT1A9/UGT2B7 glucuronidation rather than CYP450 enzymes, rendering its pharmacokinetics largely independent of CYP2D6 polymorphisms.supported
Major metabolite tapentadol-O-glucuronide has no analgesic effects. Systemic exposure to metabolites far below Ki values at MOR/NET (>45-fold). No active metabolites relevant to analgesia. mf.2010.32.1.1434165
Gastrointestinal effects (constipation, nausea) occur less frequently than with equianalgesic oxycodone.supported
Phase III RCT: tapentadol IR comparable efficacy to oxycodone IR with lower incidence of GI side effects in joint replacement surgery patients. j.clinthera.2009.02.009
Tolerance develops more slowly than with morphine in animal models, and post-marketing surveillance consistently shows lower abuse rates than comparator Schedule II opioidssupported
Tapentadol abuse event rates significantly lower than all other opioids per population-level denominators. j.jpain.2017.11.007
The residual serotonin transporter inhibition, though weaker than tramadol's, maintains a theoretical serotonin syndrome risk that post-marketing data have not confirmed at standard therapeutic dosessupported
Tapentadol inhibits NET; also inhibits SERT but less potently than tramadol. SERT inhibition may contribute to serotonin syndrome risk, particularly with MAOIs or SSRIs. bph.14105
clinical-evidence7 · 4 ok
Claim in clinical-evidence — inconclusiveinconclusiveworking →
A network meta-analysis by Freynhagen and colleagues (2021) compared tapentadol safety against other opioids across randomized controlled and withdrawal trials, concluding that tapentadol ER demonstrated a favorable safety profile relative to comparator opioids.supported
Systematic review and NMA of tapentadol PR vs other opioids for chronic pain safety. Favorable GI tolerability profile. 03007995.2020.1832977
Claim in clinical-evidence — inconclusiveinconclusiveworking →
Daniels and colleagues (2009) confirmed these findings in a randomized, double-blind, placebo-controlled Phase III trial comparing tapentadol IR with oxycodone IR for acute pain, demonstrating non-inferiority in analgesia with a significantly better gastrointestinal tolerability profile.supported
Phase III RCT showing comparable efficacy to oxycodone with fewer GI side effects in bunionectomy pain. 03007990902952825
Claim in clinical-evidence — inconclusiveinconclusiveworking →
A systematic review by Boland (2023) evaluated tapentadol for cancer pain management, finding evidence of comparable analgesia to morphine and oxycodone with potential advantages in tolerabilitysupported
Tapentadol at least as effective as morphine and oxycodone in cancer pain (5 RCTs + nonrandomized trials). Lower opioid-related toxicities including constipation and nausea. spc.0000000000000641
A controlled study by Mark and colleagues (2021) directly measured gastrointestinal function in healthy male volunteers, demonstrating that tapentadol produces less deterioration of gastric motility, transit time, and subjective GI symptoms than standard opioid therapysupported
Tapentadol causes less GI function deterioration than oxycodone at equianalgesic doses in healthy volunteers. nmo.14131
history6 · 3 ok
Claim in history — inconclusiveinconclusiveworking →
The paper established tapentadol's dual mechanism — designated "MOR-NRI" — as a first-in-class pharmacological profilesupported
Tapentadol is a novel, centrally-acting analgesic drug acting as a MOR agonist and noradrenaline reuptake inhibitor. s40263-014-0151-9
Claim in history — inconclusiveinconclusiveworking →
In November 2008, the US FDA approved tapentadol immediate release (marketed as Nucynta) for the management of moderate-to-severe acute pain in adults — a milestone described as the first approval of a new centrally acting analgesic class in 25 yearssupported
FDA approved November 2008 for acute pain, August 2011 for chronic pain ER. j.pharep.2018.01.005
The approval rested on pivotal Phase III trials in bunionectomy patients.partially supported
Phase III RCT: tapentadol IR comparable efficacy to oxycodone IR with lower incidence of GI side effects in joint replacement surgery patients. j.clinthera.2009.02.009
Claim in history — inconclusiveinconclusiveworking →
pharmacokinetic-detail6 · 3 ok
Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →
Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →
Absence of active metabolites is confirmed by Terlinden et al. 2010.supported
No active metabolites relevant to analgesia. mf.2010.32.1.1434165
The predominance of Phase II glucuronidation via UGT1A9 and UGT2B7 — rather than CYP450-mediated Phase I oxidation — fundamentally shapes tapentadol's drug-drug interaction profilesupported
No CYP metabolism; glucuronidated by UGT. s40265-021-01515-z
In an animal study, co-administration with sorafenib (a potent UGT1A1/UGT1A9 inhibitor) increased tapentadol Cmax 5.3-fold and AUC 1.5-foldpartially supported
Co-administration with sorafenib (UGT inhibitor) increased tapentadol Cmax 5.3-fold. j.biopha.2020.110530
Claim in pharmacokinetic-detail — not_supportednot supportedworking →
comparative-pharmacology5 · 2 ok
Claim in comparative-pharmacology — inconclusiveinconclusiveworking →
Claim in comparative-pharmacology — inconclusiveinconclusiveworking →
Tolerance development is comparable between tapentadol and tramadol in rodent models (31-day administration), with both compounds producing markedly less tolerance than morphine.supported
Chronic tapentadol resulted in tolerance similar to tramadol but much less than morphine. j.ejphar.2021.174245
Claim in comparative-pharmacology — inconclusiveinconclusiveworking →
Direct Phase III comparisons consistently demonstrate comparable analgesic efficacy between tapentadol and oxycodone at equipotent doses, with tapentadol showing a significantly lower incidence of gastrointestinal adverse events — approximately 40% reduction in constipation riskpartially supported
Phase III RCT: tapentadol IR comparable efficacy to oxycodone IR with lower incidence of GI side effects in joint replacement surgery patients. j.clinthera.2009.02.009
neuroscience5 · 4 ok
In vivo microdialysis confirms a +450% increase in extracellular norepinephrine in rat brain at 10 mg/kg IP, an effect absent with equianalgesic morphinesupported
Microdialysis shows +450% extracellular NE at 10 mg/kg IP. pmid:17656655
NOS inhibition with L-NOArg reverses established tapentadol tolerance and attenuates naloxone-precipitated withdrawal symptomssupported
NOS inhibitor L-NOArg reversed tapentadol tolerance. j.ejphar.2021.174245
Claim in neuroscience — inconclusiveinconclusiveworking →
However, animal conditioned place preference data suggest that tapentadol's rewarding memory formation is attenuated relative to tramadol, despite greater direct MOR activity — a finding that remains mechanistically unexplained.supported
Only tramadol retains CPP at 7/14 days. Tapentadol does not cause CPP retention despite higher CNS activity. ph16010086
Tapentadol tolerance develops approximately twice as slowly as morphine tolerance in the CCI neuropathic pain model and is comparable in magnitude to tramadol tolerance over 31 days of administrationsupported
Chronic tapentadol resulted in tolerance similar to tramadol but much less than morphine. j.ejphar.2021.174245
receptor-pharmacology4 · 1 ok
Claim in receptor-pharmacology — not_supportednot supportedworking →
This difference is clinically relevant: tramadol carries a well-established serotonin syndrome risk, whereas tapentadol's post-marketing safety data have not confirmed a serotonin syndrome signal at therapeutic doses, though isolated overdose-related cases exist.supported
Case report of probable tapentadol-induced serotonin syndrome after overdose. Only second published case of suspected tapentadol serotonin syndrome. hpj5104-320
Claim in receptor-pharmacology — inconclusiveinconclusiveworking →
Claim in receptor-pharmacology — inconclusiveinconclusiveworking →
chemistry3 · 1 ok
Claim in chemistry — inconclusiveinconclusiveworking →
Claim in chemistry — inconclusiveinconclusiveworking →
This simplified scaffold eliminates the requirement for CYP2D6-mediated metabolic activation that governs tramadol's analgesic efficacy.supported
No CYP metabolism; glucuronidated by UGT. s40265-021-01515-z
legal-status3 · 3 ok
The compound was placed in the most restrictive prescription-opioid schedules despite post-marketing evidence of lower abuse rates than comparator Schedule II opioids — a regulatory posture driven by precautionary classification based on mechanism rather than empirical abuse data.supported
Tapentadol abuse event rates significantly lower than all other opioids per population-level denominators. j.jpain.2017.11.007
The US DEA's Schedule II placement — the same schedule as morphine, oxycodone, and fentanyl — was based on tapentadol's MOR agonist mechanism and structural classification rather than empirical abuse rate data, which consistently show lower abuse event rates than all comparator opioids examined in population-level surveillancesupported
Tapentadol abuse event rates significantly lower than all other opioids per population-level denominators. Low but present public health burden. j.jpain.2017.11.007
The US DEA's Schedule II placement — the same schedule as morphine, oxycodone, and fentanyl — was based on tapentadol's MOR agonist mechanism and structural classification rather than empirical abuse rate data, which consistently show lower abuse event rates than all comparator opioids examined in population-level surveillancesupported
Postmarketing surveillance of tapentadol ER using ASI-MV. Consistently low levels of abuse and diversion. pnz250