Effexor XR 150mg 10 Caps Generic Name: venlafaxine (oral) (VEN la fax een) Brand Names: Effexor, Effexor XR What is venlafaxine? Venlafaxine is an antidepressant in a group of drugs called selective serotonin and norepinephrine reuptake inhibitors (SSNRIs). Venlafaxine affects chemicals in the brain that may become unbalanced and cause depression. Venlafaxine is used to treat major depressive disorder, anxiety, and panic disorder. Venlafaxine may also be used for purposes other than those listed in this medication guide.