Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) and a synthetic organic compound (C₁₇H₁₈F₃NO, CAS 54910-89-3) used as an active pharmaceutical ingredient in medications. It is widely employed in the treatment of major depressive disorder, helping to alleviate symptoms such as persistent sadness, lack of interest, and fatigue. It is also effective in managing obsessive-compulsive disorder (OCD), reducing the frequency and intensity of intrusive thoughts and repetitive behaviors. Additionally, it is prescribed for bulimia nervosa to help control binge-eating and purging cycles. Fluoxetine can be used to treat panic disorder, providing relief from sudden episodes of intense fear and physical symptoms like rapid heartbeat. In some cases, it is utilized for premenstrual dysphoric disorder (PMDD) to ease severe mood swings, irritability, and physical discomfort associated with the menstrual cycle. Its ability to regulate serotonin levels in the brain makes it a versatile option for various mental health conditions. As a chemical reagent, it is available as a colorless to light yellow liquid or oil with high purity (>98.5%) for pharmaceutical research and synthesis.