| Half-life | 6 hours |
| Clearance Route | mixed |
| Active Metabolites | M1 (O-desmethyltramadol), NAPQI (from paracetamol) |
| Notes | Combination PK: - Paracetamol t½ ~2 hours (hepatic) - Tramadol t½ ~6 hours (hepatic + renal) - Max 8 tablets/day (Tramadol 300 mg, Paracetamol 2600 mg) |
Severity: Moderate
Adverse Effects:
Drowsiness, dizziness, nausea, constipation; hepatotoxicity at high doses; serotonin syndrome risk; respiratory depression at high doses
Contraindications:
Severe hepatic impairment, MAOI use, uncontrolled epilepsy
Precautions:
Avoid alcohol; caution in hepatic dysfunction; CYP2D6 ultra-rapid metabolizers → higher opioid effect