fluoxetin

Fluoxetin, also known as fluoxetine, is a selective serotonin reuptake inhibitor (SSRI) antidepressant. It increases serotonin signaling in the brain by blocking its reuptake and is used to treat a range of mood and anxiety disorders. It is typically prescribed by a clinician and requires medical supervision.

Approved indications include major depressive disorder in adults and children older than eight, obsessive-compulsive disorder, bulimia nervosa, panic disorder, and premenstrual dysphoric disorder. It is sometimes prescribed for other mood or anxiety conditions and for treatment-resistant depression. Dosing is individualized and may vary by condition and patient response.

Pharmacokinetics: Fluoxetin has a relatively long half-life and an active metabolite, norfluoxetine, which contribute to a gradual onset of effect and slower withdrawal after discontinuation. It is commonly given once daily, with or without meals.

Safety and adverse effects: Common adverse effects include nausea, headache, insomnia or drowsiness, dry mouth, and sexual dysfunction. Weight changes occur in some patients. There is a risk of increased suicidal thoughts in younger people, particularly early in treatment. Serotonin syndrome can occur with other serotonergic drugs. Abrupt discontinuation can cause withdrawal symptoms, though the long half-life of fluoxetin reduces this risk. Use with MAO inhibitors or other serotonergic agents is contraindicated.

Discontinuation and interactions: Fluoxetin inhibits several cytochrome P450 enzymes, notably CYP2D6, which can raise levels of coadministered drugs. Caution is advised with NSAIDs or anticoagulants due to a potential bleeding risk.

History and availability: Fluoxetin was developed by Eli Lilly and introduced in the 1980s. It is available as a generic medication under multiple brand names, including Prozac.