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.
In 2020, it was the eighteenth most commonly prescribed medication in the United States, with more than 28 million prescriptions. It is on the World Health Organizations List of Essential Medicines. Medical uses
Depression
The evidence overall supports the efficacy of bupropion over placebo for the treatment of depression. However, the quality of evidence is low. Most meta-analyses report that bupropion has an at-most small effect size for depression. On the other hand, one meta-analysis reported a large effect size. However, there were methodological limitations with this meta-analysis, including using a subset of only five trials for the effect size calculation, substantial variability in effect sizes between the selected trials—which led the authors to state that their findings in this area should be interpreted with "extreme caution"—and general lack of inclusion of unpublished trials in the meta-analysis. Unpublished trials are more likely to be negative in findings, and other meta-analyses have included unpublished trials. Evidence suggests that the efficacy of bupropion for depression is similar to that of other antidepressants.Over the fall and winter months, bupropion prevents development of depression in those who have recurring seasonal affective disorder: 15% of participants on bupropion experienced a major depressive episode vs. 27% of those on placebo.