What is the mechanism of action (MOA) of Bupropion?

Bupropion primarily acts as a Norepinephrine-Dopamine Reuptake Inhibitor (NDRI). This mechanism involves the inhibition of the reuptake of norepinephrine and dopamine neurotransmitters in the brain, which leads to increased levels of these neurotransmitters in the synaptic cleft. This increase can help elevate mood and alleviate symptoms of depression, making bupropion an effective treatment for major depressive disorder and anxiety disorders.

Additionally, bupropion is unique compared to other antidepressants in that it does not typically affect serotonin levels, which is why it is not classified as a selective serotonin reuptake inhibitor (SSRI) or a serotonin-norepinephrine reuptake inhibitor (SNRI). Its distinct mechanism also contributes to its lower incidence of sexual side effects compared to other classes of antidepressants, making it a preferred option for certain patients.

This clear pathway of action is what differentiates bupropion from the other categories of antidepressants listed, underscoring its specific role and efficacy in managing depressive symptoms.