Fluoxetine is in a class of medications called selective serotonin reuptake inhibitors (SSRIs). It works by increasing the amount of serotonin, a natural substance in the brain that helps maintain mental balance. Fluoxetine is an antidepressant and belongs to a group of medicines known as selective serotonin reuptake inhibitors (SSRIs). This medicine works by increasing the activity of a chemical called serotonin in the brain. This medicine is available only with your doctor's prescription. Find patient medical information for Fluoxetine (Prozac, Sarafem, others) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings PROZAC ® (fluoxetine capsules, USP) is a selective serotonin reuptake inhibitor for oral administration. It is also marketed for the treatment of premenstrual dysphoric disorder (Sarafem ®, fluoxetine hydrochloride). Fluoxetine is an antidepressant medication that works in the brain. It is approved for the treatment of major depressive disorder (MDD), obsessive compulsive disorder (OCD), panic disorder, bulimia nervosa, and premenstrual dysphoric disorder (PMDD). Fluoxetine (Prozac) is a prescription antidepressant used to treat depression, OCD, bulimia, panic disorder, and PMDD. Learn about uses, dosage, side effects, and warnings. Fluoxetine, sold under the brand name Prozac, among others, is an antidepressant medication of the selective serotonin reuptake inhibitor (SSRI) class [2] used for the treatment of major depressive disorder, anxiety, obsessive–compulsive disorder (OCD), panic disorder, premenstrual dysphoric disorder, and bulimia nervosa. [2].