Venlafaxine is used to treat depression, anxiety, panic attacks, and social anxiety disorder (social phobia). It may improve your mood and energy level and may help restore your interest in daily living. It may also decrease fear, anxiety, unwanted thoughts, and the number of panic attacks. Venlafaxine is known as a serotonin-norepinephrine reuptake inhibitor (SNRI). It works by helping to restore the balance of certain natural substances (serotonin and norepinephrine) in the brain.