Which medication is an example of a selective serotonin reuptake inhibitor (SSRI)?

Fluoxetine is an example of a selective serotonin reuptake inhibitor (SSRI) because it specifically works by inhibiting the reuptake of serotonin in the brain, leading to increased serotonin levels in the synaptic cleft. This mechanism is particularly effective in treating conditions like depression, anxiety disorders, and certain other mood disorders. SSRIs like fluoxetine are known for having a favorable side effect profile compared to older antidepressants, as they primarily adjust serotonin levels without significantly affecting norepinephrine or dopamine pathways.

Citalopram, which is also an SSRI, targets similar mechanisms as fluoxetine but was not identified as the selected answer here. Venlafaxine, on the other hand, is classified as a serotonin-norepinephrine reuptake inhibitor (SNRI), which affects both serotonin and norepinephrine pathways, distinguishing it from SSRIs. Amitriptyline is a tricyclic antidepressant (TCA) that operates through a different mechanism by blocking various neurotransmitter reuptake, including serotonin and norepinephrine, and is also associated with a range of side effects, such as sedation. Hence, fluoxetine stands out as a classic example of an SSRI due to its specific action and clinical use.