A total of 17 years after its introduction,
bupropion remains a safe and effective
antidepressant, suitable for first-line use.
Bupropion undergoes metabolic transformation to an active metabolite, 4-hydroxybupropion, through hepatic
cytochrome P450-2B6 (
CYP2B6) and has inhibitory effects on
cytochrome P450-2D6 (
CYP2D6), thus raising concern for clinically-relevant drug interactions. Common side effects are nervousness and
insomnia.
Nausea appears slightly less common than with the SSRI drugs and sexual dysfunction is probably the least of any
antidepressant.
Bupropion is relatively safe in overdose with
seizures being the predominant concern. The mechanism of action of
bupropion is still uncertain but may be related to inhibition of presynaptic
dopamine and
norepinephrine reuptake transporters. The activity of vesicular monoamine transporter-2, the transporter pumping
dopamine,
norepinephrine and
serotonin from the cytosol into presynaptic vesicles, is increased by
bupropion and may be a component of its mechanism of action.
Bupropion is approved for use in major depression and
seasonal affective disorder and has demonstrated comparable efficacy to other
antidepressants in clinical trials.
Bupropion is also useful in augmenting a partial response to
selective serotonin reuptake inhibitor antidepressants, although
bupropion should not be combined with
monoamine oxidase inhibitors. It may be less likely to provoke
mania than
antidepressants with prominent serotonergic effects.
Bupropion is effective in helping people quit tobacco smoking. Anecdotal reports indicate
bupropion may lower inflammatory mediators such as
tumor necrosis factor-alpha, may lower
fatigue in
cancer and may help reduce concentration problems.