BLACK BOX WARNING
- suicidal thinking and behavior in pediatric and young adult patients
escitalopram
Brand: Lexapro
⚠ BBW Prototype: fluoxetine
Drug Class: antidepressant
Drug Family: antidepressant
Subclass: SSRI
Organ Systems: cns
Mechanism of Action
S-enantiomer of citalopram with higher SERT selectivity and potency; minimal CYP inhibition; allosteric binding site on SERT provides enhanced serotonergic effect.
serotonin reuptake transporter (SERT)
Indications
- major depressive disorder
- generalized anxiety disorder
Contraindications
- concurrent MAOIs
- concurrent pimozide
- QTc prolongation
Adverse Effects
Common
- nausea
- insomnia
- somnolence
- increased sweating
- sexual dysfunction
Serious
- QTc prolongation (dose-dependent)
- serotonin syndrome
- hyponatremia
- suicidal ideation
Pharmacokinetics (ADME)
| Absorption | ~80% bioavailability |
| Distribution | Protein binding ~56%; Vd ~12 L/kg |
| Metabolism | CYP2C19 and CYP3A4 (primary); CYP2D6 (minor) |
| Excretion | Renal and fecal |
| Half-life | 27–32 hours |
| Onset | 1–2 weeks; full effect 4–6 weeks |
| Peak | 5 hours |
| Duration | 24 hours |
| Protein Binding | 56% |
| Vd | ~12 L/kg |
Drug Interactions
| Drug / Agent | Mechanism | Severity |
|---|---|---|
| MAOIs | serotonin syndrome | major |
| CYP2C19 inhibitors (cimetidine, omeprazole) | increase escitalopram levels and QTc risk | moderate |
| QTc-prolonging drugs | additive QTc prolongation | major |
Nursing Considerations
- Obtain baseline ECG in patients with cardiac disease, electrolyte abnormalities, or concurrent QTc-prolonging medications; doses >20 mg/day increase QTc risk
- Monitor suicidal ideation especially in young adults during first 4 weeks and after dose changes
- Assess for hyponatremia in elderly patients and those taking diuretics — check serum sodium if confusion or lethargy develops
- Taper on discontinuation over several weeks to prevent discontinuation syndrome (dizziness, 'brain zaps,' irritability)
Clinical Pearls
- Escitalopram is frequently cited as having the best tolerability and fewest drug interactions among SSRIs — the S-enantiomer is 30 times more potent at SERT than the R-enantiomer of citalopram
- The FDA issued a safety communication limiting citalopram (not escitalopram) to 40 mg/day due to QTc concerns — escitalopram has a similar but less severe QTc dose-response relationship
Safety Profile
Pregnancy use-with-caution
Lactation use-with-caution
Renal Adjustment Not required
Hepatic Adjustment Required
TDM Not required
Concordance Terms
Cross-referenced clinical concepts — click any term to see all content where it appears.