Quitting smoking: Can an antidepressant improve the success rate?

People who want to quit smoking can increase their chances of short-term success by taking the antidepressant bupropion. But side effects are common, so any use of this drug needs to be carefully considered.

Many people who smoke want to quit someday, or they have even tried to quit once or several times. The problem is, it is not easy to stay off cigarettes. There are some ways to increase the chances of success at least somewhat, though, especially using nicotine replacement therapy (NRT) such as nicotine patches or gum. You can read more about NRT in the research summary “Quitting smoking: How much do nicotine patches and gum help?”. Because NRT also has only had very limited success, researchers are still trying to find other options.

One of these options is the group of drugs called antidepressants – drugs that are normally used to treat depression. Some of these drugs have already been tested to see if they can help people quit smoking. To see what the state of the evidence is, researchers from the Cochrane Collaboration looked for reliable trials where anti-depressants were tested for quitting smoking.

After evaluating a total of 66 trials, the researchers came to the conclusion that for most types of antidepressants there is no evidence to show that they are suitable for quitting smoking. Researchers did find some trials that provided conclusive evidence that two types increase the chance of giving up smoking. However, only one of those, bupropion, is approved for use for quitting smoking internationally, including in Germany. In 36 trials involving a total of a little more than 11,000 people, half of them used bupropion, while the other half took a fake drug (placebo).

The results: out of 100 people who smoked who used bupropion, 81 went back to smoking. In comparison, out of 100 smokers who did not use bupropion, 89 had started smoking again after 6 to 12 months. In other words, the drug had helped an extra 1 out of 10 smokers to quit.

In deciding whether or not to use bupropion or other antidepressants, though, the question of adverse effects plays an important role, too. Taking bupropion caused sleeping disorders in about an additional 1 to 3 out of 10 people. Other side effects were dry mouth and nausea. There is also a small risk of seizures. So using this drug might be dangerous for people at risk of having seizures. Because there can sometimes be serious adverse effects, the Cochrane researchers suggest that the use of bupropion needs to be carefully considered.

The US regulatory authority FDA issued a safety warning on the basis of new reports in July 2009. Some people had depression or suicidal thoughts or acted strangely after using bupropion. The FDA emphasizes that these symptoms also affected some people who had not had any psychological disorders before, as well as those who had not quit smoking despite using the drug. This suggests that the changes in mood are not caused solely by quitting smoking, but could be caused by the drug itself. The agency recommends that people who use the drug are better informed about possible adverse effects.

The FDA advises both people who take bupropion as well as their doctors to watch for any signs of changes in mood or behavior that do not normally occur in people who quit smoking. In particular, these include depression, irritability and suicidal thoughts. The FDA recommends stopping use of the drug and seeking medical advice if such symptoms occur.

Author: Institute for Quality and Efficiency in Health Care (IQWiG)

© IQWiG (Institute for Quality and Efficiency in Health Care)