How it works

Bupropion is an antidepressant that may also be used to aid in the cessation of smoking.

Experts are unsure how bupropion works in depression, but it was previously thought to be because of its ability to inhibit the reuptake of two neurotransmitters, norepinephrine, and dopamine (although this reuptake inhibition is weak). Bupropion has no effect on serotonin reuptake or inhibits monoamine oxidase. Despite the fact that the mechanism by which bupropion works is unknown, studies show that it is still effective in treating mood disorders such as depression.

Bupropion is thought to be effective for smoking cessation because it increases dopamine levels in the nerve synapse by inhibiting dopamine reuptake. This compensates for the dopamine deficiency that occurs during nicotine withdrawal (nicotine causes a release of dopamine which enhances the pleasure-seeking pathways in the brain; reducing nicotine intake means these pathways are no longer being stimulated; bupropion counteracts this effect).

Bupropion is an aminoketone antidepressant that is chemically distinct from all other antidepressants.