Celexa is an antidepressant prescription medicine used to treat depression and major depressive disorder. Celexa may cause serious side effects. Celexa (citalopram) is a prescription drug that treats depression in adults. Learn about side effects, Celexa vs. Lexapro, dosage, withdrawal, and more. Overview: Citalopram is used to treat depression. It is thought to work by increasing the amount of a natural chemical called serotonin in the brain. Common side effects may include nausea, changes. Learn about citalopram (Celexa) usage and dosing. Read the latest news and reviews about the drug as well as potential side effects and popular alternatives. Citalopram is a prescription medicine used in adults to treat depression. Citalopram is also used to treat major depressive disorder (MDD). Citalopram belongs to a class of antidepressants called selective serotonin reuptake inhibitors (SSRIs). Citalopram, sold under the brand name Celexa among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. [7][9] It is used to treat major depressive disorder, obsessive–compulsive disorder, panic disorder, and social anxiety disorder. [7] Celexa (citalopram) is a brand-name drug that’s used to treat depression in adults. Celexa comes as a tablet that you swallow. Learn about side effects, dosage, uses, and more. Take this medicine only as directed by your doctor, to benefit your condition as much as possible. Celexa is a selective serotonin reuptake inhibitor (SSRI) that blocks the reuptake of serotonin (5-HT) by the nerves of the central nervous system, which enhances serotonergic activity. Celexa (citalopram hydrobromide) used to treat the symptoms of depression. Learn side effects, dosage, drug interactions, warnings, patient labeling, reviews, and more.