What is the mechanism of action for bupropion?

Bupropion's mechanism of action is primarily as a norepinephrine (NE) and dopamine (DA) reuptake inhibitor. This means that it works by inhibiting the reuptake of these neurotransmitters back into the presynaptic neuron, thereby increasing their availability in the synaptic cleft. This action is beneficial for treating disorders like major depressive disorder and for aiding in smoking cessation, as it enhances mood and mitigates cravings.

The enhancement of both norepinephrine and dopamine levels is key to its therapeutic effects. Unlike many antidepressants, it does not primarily act on the serotonin system, which distinguishes it within its class. Moreover, bupropion does not have a significant affinity for serotonin receptors or act as a GABA antagonist, making those options less applicable in describing its mechanism. Understanding this highlights how bupropion serves different clinical roles compared to other antidepressants while leveraging the crucial neurotransmitters involved in mood regulation and addiction.