BACKGROUND: Bupropion has been available in the United States since 1989. 
Initially a thrice-daily immediate-release formulation, a twice-daily 
sustained-release formulation followed in 1996, and, in August 2003, a 
once-daily extended-release formulation was introduced. On the 15th anniversary 
of its introduction, we undertook a review of the background/history, mechanism 
of action, formulations, and clinical profile of bupropion.
DATA SOURCES: Major efficacy trials and other reports were obtained and reviewed 
from MEDLINE searches, review of abstracts from professional meetings, and the 
bupropion SR manufacturer's databases. Searches of English-language articles 
were conducted from June 2003 through August 2004. No time limit was specified 
in the searches, which were conducted using the search terms bupropion, 
bupropion SR, and bupropion XL.
DATA SYNTHESIS: Bupropion inhibits the re-uptake of norepinephrine and dopamine 
neurotransmission without any significant direct effects on serotonin 
neurotransmission. Bupropion is an effective antidepressant with efficacy 
comparable to selective serotonin reuptake inhibitors and other antidepressants. 
It is well tolerated in short-and longer-term treatment. Headache, dry mouth, 
nausea, insomnia, constipation, and dizziness are the most common adverse 
events. Seizure and allergic reactions are medically important adverse events 
associated with bupropion and are reported rarely. Among all the newer 
antidepressants in the United States, bupropion appears to have among the lowest 
incidence of sexual dysfunction, weight gain, and somnolence. Although not U.S. 
Food and Drug Administration approved for these indications, bupropion has also 
been used as an adjunctive treatment to reverse antidepressant-induced sexual 
dysfunction and to augment anti-depressant efficacy in partial responders and 
non-responders to other agents.
CONCLUSION: Bupropion has played and will continue to play an important role as 
a treatment for major depressive disorder in adults, as well as for other 
related disorders.