Sertraline is a prescription antidepressant (SSRI) used to treat major depressive disorder, panic disorder, post-traumatic stress disorder (PTSD), social anxiety disorder, and premenstrual dysphoric disorder (PMDD). It is also used to treat obsessive-compulsive disorder (OCD) in adults and children aged 6-17. It improves mood, sleep, and appetite while reducing fear and unwanted thoughts.