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Opioid Analgesic (Weak-Moderate) / SNRI Pregnancy: Avoid prolonged use and near delivery — neonatal withdrawal, respiratory depression

Tramadol

Brand names: Zamadol, Tramquel, Tilodol SR

Adult dose

Dose: Immediate release: 50–100 mg every 4–6 hours. Modified release: 100–200 mg BD. Maximum: 400 mg/day.
Route: Oral (or IV in hospital)
Frequency: QDS (IR) or BD (MR)
Max: 400 mg/day (300 mg/day in elderly)
Dual mechanism: weak mu-opioid agonist + serotonin/noradrenaline reuptake inhibition. Serotonin syndrome risk with SSRIs, SNRIs, MAOIs, triptans. Lowers seizure threshold.

Paediatric dose

Dose: 1 mg/kg
Route: Oral or IV
Frequency: Every 4–6 hours PRN
Max: 400 mg/day
Concentration: 50 mg/mL injection; 50 mg capsules mg/ml
Licensed for children ≥12 years. Use with caution. Not recommended in children <12 years.

Dose adjustments

Renal

Maximum 200 mg/day if eGFR <30; increase dosing interval to every 12 hours

Hepatic

Maximum 200 mg/day in hepatic impairment; increase dosing interval

Paediatric weight-based calculator

Licensed for children ≥12 years. Use with caution. Not recommended in children <12 years.

Clinical pearls

  • Serotonin syndrome warning: tramadol + SSRI combination is common and potentially dangerous — assess risk in all patients
  • Lower seizure threshold: avoid in patients with epilepsy; risk further increased with SSRIs
  • Withdrawal syndrome occurs with abrupt discontinuation — taper dose
  • Not a GABA-B agonist like gabapentinoids — different mechanism from pregabalin/gabapentin despite occasional prescribing in similar pain contexts

Contraindications

  • Concurrent MAOIs or within 14 days of stopping
  • Uncontrolled epilepsy
  • Respiratory depression
  • Acute alcohol/opioid/psychotropic drug intoxication

Side effects

  • Nausea/vomiting (common — premedicate with metoclopramide)
  • Dizziness
  • Constipation (less than codeine)
  • Seizures (especially with SSRIs)
  • Serotonin syndrome (with SSRIs, MAOIs)
  • Dependence/withdrawal
  • Sweating

Interactions

  • SSRIs/SNRIs — serotonin syndrome risk (significant interaction)
  • MAOIs — severe serotonin syndrome (absolutely contraindicated)
  • Carbamazepine — reduces tramadol efficacy and increases seizure risk
  • Warfarin — may enhance anticoagulant effect (monitor INR)
  • Antidepressants — multiple serotonergic interactions

Monitoring

  • Pain scores
  • Nausea (consider anti-emetic cover)
  • Neurological symptoms (serotonin syndrome: hyperthermia, clonus, agitation)
  • Seizure risk assessment

Reference: BNFc; BNF; MHRA Drug Safety Update on Serotonin Syndrome. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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