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Thomas S. May, M.A.Medical Writer |
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Zyban: Helps Kick Habit--or Bucket?
Thomas S. May, Medical Writer
Introduction David Landry was a seemingly healthy 26-year-old man living in Montreal, Canada. In January of this year, he decided to give up smoking with the help of Zyban (bupropion). Ten days after taking his first pill, his girlfriend found him lying dead on the kitchen floor. Charles Hammock, another Montreal resident, was 48 when he died suddenly in August 1999--also less than 2 weeks after starting treatment with Zyban. According to the provincial coroner's office, his death was caused by a fatal arrhythmia (irregular heartbeat). Landry and Hammock are just two of the dozens (and possibly hundreds) of people who have died while taking Zyban. Official statistics are not readily available for the United States, but the drug is being investigated as the possible cause of at least five deaths in Canada, as well as 19 in Britain and Australia.
Besides the deaths, several
thousand "adverse events" have been reported in connection with Zyban.
These include grand mal (major) seizures and various psychotic episodes,
as well as nonfatal heart attacks and strokes.
Association Denied Zyban has the same active ingredient as the antidepressant medication Wellbutrin--bupropion hydrochloride. It is the first non-nicotine drug treatment that has been approved for people trying to stop smoking in Canada, the United States, Australia, Britain, and some other European countries. GlaxoSmithKline, manufacturer of Zyban, denies there is any connection between its product and the deaths of people who had been taking it. "People who smoke are at greatly increased risk. They are about five times more likely than nonsmokers are to have a heart attack or heart problems. So these events occurring in a patient population which is taking the medication don't necessarily implicate the medication as the cause," says Anne Phillips, MD, Glaxo Canada's vice president of research and development. Nigel Higson, a general practitioner in the United Kingdom, agrees: "Most smokers who consult their physicians for help with smoking have been shocked into doing something about their habit. Perhaps they are getting chest pain or shortness of breath. Hence, there is a greater chance of dying as a result of their underlying condition, irrespective of what treatment is given to the patient to assist the quitting process," he says.
Taylor Hays, MD, was involved in
some of the clinical trials that tested the drug's safety and
effectiveness. He also says he doubts that Zyban has been responsible for
the deaths. "I can tell you from my own experience in clinical trials with
bupropion that I have seen no life-threatening reactions and nothing that
would lead me to believe that the drug is not safe for most individuals,"
he says.
Serious Side Effects Some experts say there is reason to be concerned about Zyban. Christopher Harrison, another British physician, says that about 10% of his patients had to stop using Zyban because they experienced some serious side effects after taking the drug for a few days. "It is often the case that the frequency of adverse events only becomes apparent once a drug is prescribed more frequently, as opposed to the highly artificial environment of clinical trials," Harrison says.
In a letter to the editor of the British Medical Journal, Dr. Herbert Kinnel, a medical advisor to the Berkshire Diet Centre, also points out that the chemical structure of bupropion hydrochloride is similar to that of amphetamines--powerful stimulants that have been linked to many deaths worldwide.
Some of the side effects listed in the patient information for Zyban also show that it is a stimulant capable of causing serious adverse reactions, including
Significant increases in blood pressure have also occurred in some patients on Zyban. "In clinical practice, hypertension, in some cases severe, requiring acute treatment, has been reported in patients receiving bupropion," the product literature states.
Should You Use It? Some studies suggest that smokers who are very highly motivated to stop smoking can double their chances of quitting with the help of Zyban. Nevertheless, the drug is not recommended for people who are not firmly committed to giving up smoking: It has not been shown to work well in these people. Also, because of the dangers of serious adverse reactions, bupropion hydrochloride should not be taken by those who
Zyban should not be prescribed to patients with uncontrolled hypertension, because the drug may raise their blood pressure to dangerously high levels. No one with a history of serious head trauma, brain tumor, brain surgery, or stroke should take Zyban because there is an increased risk of seizures in these patients. We
don't know for sure whether Zyban has actually caused (or contributed to)
any of the deaths that have occurred in people using it. Nevertheless, "It
is clear that patients must be carefully selected to rule out anyone with
contraindications," according to Richard Vautrey, a general practitioner
in the United Kingdom. "Major problems are likely to have occurred if this
selection was not done properly," he says.
Thomas S. May is a medical
journalist based in Toronto, Ontario, Canada. He has a master's degree in
psychology from Simon Fraser University in Burnaby, British Columbia. Source: Medscape Health
Reprinted from Medscape Health for Consumers.
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