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Dopamine/Noradrenaline Reuptake Inhibitor (DNRI) — Smoking Cessation Pregnancy: Avoid unless essential — limited data

Bupropion (Smoking Cessation)

Brand names: Zyban

Adult dose

Dose: 150 mg OD × 6 days, then 150 mg BD (minimum 8h between doses). Duration 7–9 weeks.
Route: Oral (swallow whole — do not crush)
Frequency: OD for 6 days, then BD
Max: 300 mg/day
Set quit date for week 2 of treatment (continue smoking during first week). Lowers seizure threshold — avoid in patients with seizure risk. Last dose no later than 6pm to prevent insomnia.

Paediatric dose

Route: N/A
Frequency: N/A
Max: Not licensed in children
Not applicable in paediatric patients

Dose adjustments

Renal

Reduce dose — 150 mg OD throughout in renal impairment

Hepatic

Reduce dose — 150 mg OD throughout in hepatic impairment

Clinical pearls

  • Smoking cessation: start 1 week before quit date — drug takes time to reach therapeutic levels
  • Seizure risk: dose-dependent; avoid doses >150 mg in at-risk patients; take last dose before 6pm to limit peak levels
  • Useful in patients with depression and smoking — dual benefit (antidepressant at higher doses)
  • Available as varenicline for smoking cessation — may be more effective but review psychiatric history first

Contraindications

  • Epilepsy or seizure history
  • Eating disorders (anorexia/bulimia — seizure risk)
  • Bipolar disorder
  • Abrupt alcohol/benzodiazepine withdrawal (seizure risk)
  • MAOIs within 14 days

Side effects

  • Insomnia (common — take last dose before 6pm)
  • Dry mouth
  • Headache
  • Nausea
  • Agitation
  • Seizures (dose-related — 0.1% at 300 mg/day)
  • Hypertension

Interactions

  • MAOIs — seizures/serotonin syndrome (contraindicated)
  • Antipsychotics/TCAs — lower seizure threshold (additive)
  • Tamoxifen — bupropion reduces tamoxifen activation (CYP2D6 inhibition)

Monitoring

  • Seizure risk assessment before starting
  • Blood pressure (baseline and periodic)
  • Mood changes
  • Insomnia
  • Smoking cessation status at 4 and 8 weeks

Reference: BNFc; BNF; NICE PH10 Smoking Cessation; Zyban SPC. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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