Cigarette dependence is recognised as a life-threatening disorder which can be treated by behavioural support and/or medication. Bupropion hydrochloride sustained-release (Zyban trade mark, GlaxoSmithKline) is licensed in many countries including the US, Canada, UK, Australia and continental Europe to aid smoking cessation. The usual recommended dose is 150 mg b.i.d. taken for 7 - 14 days prior to the quit date, and then 6 - 8 weeks afterwards (figures vary across countries). Evidence from seven double-blind, placebo-controlled, randomised trials shows that it improves success at staying off cigarettes for at least 12 months by 9 - 10 percentage points. Taking into account estimates of subsequent cessation and relapse patterns in treated and untreated smokers, and the improvement in life-expectancy of smokers who manage to stop, the estimated cost/life/year saved from an episode of use of the medication is approximately UK pound 1000 or US$1500. Bupropion has CNS stimulant properties; the common side effects are dry mouth and sleep disturbance. Rare but serious side effects are anaphylactic/hypersensitivity reaction and seizure (both estimated at 1 in a 1000). The drug is contraindicated in patients with hypersensitivity to the drug or its metabolites, any seizure disorder, eating disorder, severe hepatic cirrhosis, history of bipolar disorder or in patients taking monoamine oxidase inhibitors. Extreme caution is advised where there are any predisposing factors that may reduce the seizure threshold. Bupropion sustained-release and nicotine replacement therapies are both considered as first-line treatments to aid smoking cessation. Ideally patients should also enrol in a structured behavioural support programme to boost their chances of success.