Which of the following medications is classified as a tricyclic antidepressant?

Imipramine is classified as a tricyclic antidepressant (TCA) because it is part of a group of medications that were first developed in the 1950s and are characterized by their three-ring chemical structure. TCAs work by inhibiting the reuptake of neurotransmitters such as serotonin and norepinephrine, increasing their levels in the brain, which is thought to be important in alleviating symptoms of depression.

Other choices, such as Duloxetine and Venlafaxine, belong to a newer class of antidepressants known as serotonin-norepinephrine reuptake inhibitors (SNRIs), which also work by affecting neurotransmitter levels but have a different chemical structure and mechanism of action. Fluoxetine, on the other hand, is a selective serotonin reuptake inhibitor (SSRI), which primarily targets serotonin reuptake specifically. By understanding the classification and mechanisms of these medications, one can better grasp the pharmacological approaches available for treating depressive disorders.