Which of the following is NOT a type of antidepressant listed?

Beta-blockers are not classified as antidepressants. Instead, they are primarily used to manage cardiovascular conditions, such as hypertension and arrhythmias, as well as to prevent migraines and treat anxiety symptoms related to performance situations. While they can have anxiolytic effects, their primary mechanism of action involves blocking beta-adrenergic receptors, which is different from how antidepressants function.

In contrast, SSRIs (selective serotonin reuptake inhibitors), SNRIs (serotonin-norepinephrine reuptake inhibitors), and tricyclics are all established classes of antidepressants that work by altering neurotransmitter levels in the brain, specifically targeting serotonin and/or norepinephrine to help alleviate symptoms of depression and anxiety. Each of these classes has a unique mechanism and is indicated for the treatment of various mood disorders, confirming their status as antidepressants.