Bupropion hydrochloride, sold under the brand names of Zyban® and Wellbutrin®, is a drug used to help people quit smoking. Originally marketed as an anti-depressant, bupropion can also help reduce cravings for nicotine. Most bupropion side effects are mild, but for some people they can be more dangerous.
The most common bupropion side effects are weight loss and dry mouth. The drug is a serotonin, dopamine, and norepinephrine uptake inhibitor, and these changes in brain chemistry can result in changes in appetite. Many patients using bupropion are not bothered by losing weight, because weight gain is common side effect of quitting smoking. Dry mouth can be relieved by avoiding caffeine drinks and sipping water or sugarless drinks throughout the day. Patients can also use a humidifier at night to prevent dry mouth.
Two other common bupropion side effects are headaches and constipation, which are common side effects of most anti-depressants. Also quite common are nausea, vomiting, dizziness, and increased sweating. For some people, taking the drug with food helps to alleviate these symptoms, while others might find they are more comfortable if they take the drug before going to sleep. Insomnia, however, is also a commonly reported side effect, so taking the drug at bedtime could actually make this symptom worse.
Less common but perhaps more worrying bupropion side effects are hallucinations, hostility, aggression, and suicidal ideation. These side effects have been reported by users with no prior history of psychiatric problems. One reason for this might be that aggression, depression, and suicidal ideation are also possible side effects of smoking cessation, and have been reported even by patients not using the drug. People who are prescribed a drug containing bupropion are strongly advised to stop taking it and report any changes in behavior or feelings of depression to their doctors immediately.
Bupropion is not a nicotine substitute. Instead, it causes changes in the brain that make people trying to quit smoking crave cigarettes less, and it may even make smoking feel less pleasurable. This benefit of bupropion was discovered by accident from observing people using it as an anti-depressant. It is generally used as part of a larger smoking-cessation program that includes therapy and nicotine replacement like gum or patches. Patients who used this drug while trying to quit reported a significantly higher success rate in the first six months than people who used a placebo.