Which of the following is NOT an example of an MAOI?

Paxil is the correct answer because it is not an MAOI (Monoamine Oxidase Inhibitor). Instead, Paxil, which is the brand name for paroxetine, is a selective serotonin reuptake inhibitor (SSRI) used primarily to treat depression and anxiety disorders.

MAOIs, like Marplan, Nardil, and Parnate, work by inhibiting the action of the monoamine oxidase enzyme, which breaks down neurotransmitters like serotonin, norepinephrine, and dopamine, thus increasing their availability in the brain. This mechanism differs significantly from that of SSRIs, which specifically target serotonin levels without affecting norepinephrine or dopamine directly. Recognizing the classification and action of each medication is crucial for understanding their therapeutic uses and potential dietary interactions, particularly with MAOIs which require avoiding tyramine-rich foods to prevent hypertensive crises.