Bupropion, sold under the brand names Wellbutrin and Zyban among others, is an atypical antidepressant primarily used to treat major depressive disorder and to support smoking cessation. It is also popular as an add-on medication in the cases of "incomplete response" to the first-line selective serotonin reuptake inhibitor (SSRI) antidepressant. Bupropion has several features that distinguish it from other antidepressants: it does not usually cause sexual dysfunction; it is not associated with weight gain and sleepiness, and it is more effective than SSRIs at improving symptoms of hypersomnia and fatigue. Bupropion does, however, carry a much higher risk of seizure than many other antidepressants and extreme caution must be taken in patients with a history of seizure disorder. Common adverse effects of bupropion with the greatest difference from placebo are dry mouth, nausea, constipation, insomnia, anxiety, tremor, and excessive sweating. Raised blood pressure is notable. Rare but serious side effects include seizure, liver toxicity, psychosis, and risk of overdose. Bupropion use during pregnancy may be associated with increased odds of congenital heart defects.Bupropion acts as a norepinephrine–dopamine reuptake inhibitor and a nicotinic receptor antagonist. However, its effects on dopamine are weak. Chemically, bupropion is an aminoketone that belongs to the class of substituted cathinones and more generally that of substituted amphetamines and substituted phenethylamines.Bupropion was invented by Nariman Mehta, who worked at Burroughs Wellcome, in 1969. It was first approved for medical use in the United States in 1985. Bupropion was originally called by the generic name amfebutamone, before being renamed in 2000.
Bupropion also improves depression in bipolar disorder, with the efficacy and risk of affective switch being similar to other antidepressants.Bupropion has several features that distinguish it from other antidepressants: for instance, unlike the majority of antidepressants, it does not usually cause sexual dysfunction, and the occurrence of sexual side effects is not different from placebo. Bupropion treatment is not associated with weight gain; on the contrary, the majority of studies observed significant weight loss in bupropion-treated participants. Bupropion treatment also is not associated with the sleepiness that may be produced by other antidepressants. Bupropion is more effective than selective serotonin reuptake inhibitors (SSRIs) at improving symptoms of hypersomnia and fatigue in depressed patients. There appears to be a modest advantage for the SSRIs compared to bupropion in the treatment of depression with high anxiety; they are equivalent for depression with moderate or low anxiety.The addition of bupropion to a prescribed SSRI is a common strategy when people do not respond to the SSRI, and it is supported by clinical trials; however, it appears to be inferior to the addition of atypical antipsychotic aripiprazole. Smoking cessation
Prescribed as an aid for smoking cessation bupropion reduces the severity of craving for tobacco and withdrawal symptoms such as depressed
mood, irritability, difficulty concentrating, and increased appetite. Initially, bupropion slows the weight gain that often occurs in the first weeks after quitting smoking.