Venlafaxine is a type of antidepressant medication belonging to the class of serotonin-norepinephrine reuptake inhibitors (SNRIs). It is commonly prescribed to treat major depressive disorder, generalized anxiety disorder, social anxiety disorder, and panic disorder. Venlafaxine works by increasing the levels of the neurotransmitters serotonin and norepinephrine in the brain, which helps improve mood and alleviate anxiety.