Is bupropion (Zyban) causing deaths?

To the Editor: From 1 February to 30 June 2001, 277 602 prescriptions for the smoking cessation drug bupropion hydrochloride (Zyban, GlaxoSmithKline) were processed. The Health Insurance Commission approved 343 737 prescriptions for bupropion between 1 February and 30 June.1 Comparing this figure with the 277 602 processed scripts, some 66 135 (19.2%) scripts went unfilled. One reason for this may have been extensive publicity given to reports of deaths and numerous adverse reactions following bupropion use.

The website of the Australian Drug Reactions Advisory Committee (ADRAC) reports that, as at 22 June, there had been 18 reports of deaths in patients aged from 30 years to 69 years who were using or who had recently stopped using bupropion.2 ADRAC summarised intelligence on these deaths thus:

Smokers are at 3.1 times greater risk of dying (from any cause) than non-smokers and twice as likely to die from coronary disease and stroke.3 People with depression are three times as likely to be daily smokers4 and have double the suicide rate of non-smokers.5

In Australia, sudden coronary fatalities occur at a rate of about 450 per million people aged under 65,6 perhaps at a rate of 355 per million in non-smokers and about double that in smokers. In three months (the period of recommended bupropion use), one would expect 180 deaths per million smoker-users. Thus, among 277 602 Australian smokers, 50 might die during any given three-month period without any added risk from bupropion. This estimate helps to place the 18 fatalities reported to ADRAC in context.

The 277 602 scripts represent about 9.5% of Australia's 2.9 million regular smokers. These people, their families and doctors deserve to have their anxieties about the risks of using bupropion addressed. We would urge the government to commission urgently a case–control study of morbidity and mortality among smokers and their relationships to use or non-use of bupropion.