Escitalopram, sold under the brand names Lexapro and Cipralex, among others, is an antidepressant medication of the selective serotonin reuptake inhibitor (SSRI) class.

Common side effects include headache, nausea, sexual problems, mild sedation, and trouble sleeping.

[15] The drug is often found to have superior efficacy to other antidepressants in alleviating the symptoms of depression and anxiety, followed by another SSRI, sertraline, but escitalopram is less likely to trigger diarrhea and nausea.

[30][needs update] Escitalopram, like other SSRIs, has been shown to affect sexual function, causing side effects such as decreased libido, delayed ejaculation, and anorgasmia.

[33][34][35] The authors of a related study note the general problem with statistical approaches: due to the rarity of suicidal events in clinical trials, it is hard to draw firm conclusions with a sample smaller than two million patients.

[36] Citalopram and escitalopram are associated with a mild dose-dependent QT interval prolongation,[37] which is a measure of how rapidly the heart muscle repolarizes after each heartbeat.

Prolongation of the QT interval is a risk factor for torsades de pointes (TdP), a heart rhythm disturbance that is sometimes fatal.

[41][42] The US Food and Drug Administration and Health Canada did not similarly order restrictions on escitalopram dosage, only on its predecessor citalopram.

[43] Like other SSRIs, escitalopram has also been reported to cause hyponatremia (low sodium levels), with rates ranging from 0.5 to 32%, which can often be attributed to SIADH.

[53] Other symptoms may be genital anesthesia, anhedonia, decreased libido, vaginal lubrication issues, and nipple insensitivity in women.

Frequent symptoms in one study were dizziness (44%), muscle tension (44%), chills (44%), confusion or trouble concentrating (40%), amnesia (28%), and crying (28%).

[58] There have been spontaneous reports of discontinuation of escitalopram and other SSRIs and SNRIs, especially when abrupt, leading to dysphoric mood, irritability, agitation, anxiety, headache, lethargy, emotional lability, insomnia, and hypomania.

Other symptoms such as panic attacks, hostility, aggression, impulsivity, akathisia (psychomotor restlessness), mania, worsening of depression, and suicidal ideation can emerge when the dose is adjusted down.

Therapeutic blood levels of escitalopram are usually in the range of 20–80 μg/L but may reach 80–200 μg/L in the elderly, patients with hepatic dysfunction, and those who are poor CYP2C19 metabolizers or following acute overdose.

[63] Combination of citalopram with fluoxetine or fluvoxamine resulted in increased exposure to the escitalopram enantiomer, owing to the strong inhibition of CYP2C19 and CYP2D6 by these agents.

[64] Escitalopram should be taken with caution when using St. John's wort, ginseng, dextromethorphan (DXM), linezolid, tramadol, and other serotonergic drugs due to the risk of serotonin syndrome.

[67] Escitalopram, similarly to other SSRIs, may increase bleeding risk with NSAIDs (ibuprofen, naproxen, mefenamic acid), antiplatelet drugs, anticoagulants, omega-3 fatty acids, vitamin E, and garlic supplements due to escitalopram's inhibitory effects on platelet aggregation via blocking serotonin transporters on platelets.

These drugs include antiarrhythmics, antipsychotics, tricyclic antidepressants, some antihistamines (astemizole, mizolastine), macrolide and fluoroquinolone antibiotics, some 5-HT3 receptor antagonists (except palonosetron), and some antiretrovirals (ritonavir, saquinavir, lopinavir).

Over time, this leads to a downregulation of pre-synaptic 5-HT1A receptors, which is associated with an improvement in passive stress tolerance, and delayed downstream increase in expression of brain-derived neurotrophic factor, which may contribute to a reduction in negative affective biases.

The short time (3.5 years) it took to develop escitalopram can be attributed to the previous experience of Lundbeck and Forest with citalopram, which has similar pharmacology.

[77] Escitalopram is sold under many brand names worldwide such as Cipralex, Lexapro, Lexam, Mozarin, Aciprex, Depralin, Ecytara, Elicea, Gatosil, Nexpram, Nexito, Nescital, Szetalo, Stalopam, Pramatis, Betesda, Scippa and Rexipra.