Tapentadol
Brand: Nucynta / Palexia
Analgesic
Opioid analgesic (µ-opioid agonist + norepinephrine reuptake inhibitor)
Pharmacokinetics
| Half-life | 4 hours |
| Tmax | 1.5 h |
| Bioavailability | 32 % (approx) |
| Protein Binding | 20 % |
| Volume of Distribution | 7 L/kg (approx) |
| Clearance Route | hepatic |
| Active Metabolites | no |
| Notes | Primarily metabolized by glucuronidation (UGT1A9, UGT2B7); minimal CYP involvement; metabolites are largely inactive. |
⚠️ Safety & Warnings
Severity: Severe
Adverse Effects:
Nausea, vomiting, dizziness, somnolence, constipation, headache, respiratory depression
Contraindications:
Severe respiratory depression, acute/severe bronchial asthma, paralytic ileus, concurrent MAOI use
Precautions:
Risk of dependence, abuse and withdrawal; caution in elderly, hepatic impairment, head injury and seizure disorders; avoid alcohol and other CNS depressants