Last reviewed 2026-04-22 · How we verify

citalopram (celexa)

Citalopram selectively inhibits the reuptake of serotonin at the neuronal synapse, increasing serotonin availability in the brain.

Citalopram selectively inhibits the reuptake of serotonin at the neuronal synapse, increasing serotonin availability in the brain. Used for Major depressive disorder, Panic disorder.

At a glance

Mechanism of action

Citalopram is a selective serotonin reuptake inhibitor (SSRI) that blocks the serotonin transporter protein, preventing the reabsorption of serotonin from the synaptic cleft back into presynaptic neurons. This increases serotonin concentration in the extracellular space, enhancing serotonergic neurotransmission. This mechanism is thought to improve mood and reduce anxiety symptoms in depression and related disorders.

Approved indications

• Major depressive disorder
• Panic disorder

Common side effects

• Nausea
• Somnolence
• Dry mouth
• Sweating
• Tremor
• Diarrhea
• Insomnia
• Sexual dysfunction

Key clinical trials

• Dynamic Networks in Depression Treatment: Mechanisms of Change in Pharmacological, Psychological and Combined Treatment of Depression (PHASE4)
• TDM-Guided Treatment With SSRIs in Hospitalized Adults and Children (PHASE4)
• Efficacy and Mechanisms of Escitalopram in Drug-Naïve First-Episode Major Depressive Disorder (NA)
• Citalopram as a Posterior Cortical Protective Therapy in Parkinson Disease (PHASE2)
• Acupuncture and Escitalopram for Treating Major Depression Clinical Study (NA)
• Pattern Separation in Major Depressive Disorder (PHASE1)
• Optimized Predictive Treatment In Medications for Unipolar Major Depression (OPTIMUM-D) (PHASE4)
• Treatment of Psoriasis With Depression and/or Anxiety With Methotrexate vs Combined Methotrexate and Antidepressant (PHASE4)

Primary sources

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