What is the correct dosing regimen for prescribing Lexapro (escitalopram)?

Prescribing Lexapro (Escitalopram): Dosing Regimen

Start escitalopram at 10 mg once daily for most adults with major depressive disorder or generalized anxiety disorder, taken in the morning or evening with or without food. 1

Standard Adult Dosing

• Initial dose: 10 mg once daily for both major depressive disorder (MDD) and generalized anxiety disorder (GAD) 1
• Timing: Once daily, morning or evening, with or without food 1
• Dose escalation: If increasing to 20 mg, wait a minimum of 1 week after starting 10 mg 1
• Maximum dose: 20 mg daily for standard adult populations 1

The FDA label establishes that 10 mg is effective for most patients, and while 20 mg was also effective in trials, it did not demonstrate greater benefit than 10 mg in fixed-dose studies for depression 1. However, research suggests 10 mg is optimal for moderate depression, while 20 mg may be needed for severe depression 2.

Adolescent Dosing (12-17 years)

• Initial and recommended dose: 10 mg once daily 1
• If escalating to 20 mg: Wait minimum of 3 weeks (longer than adults) 1
• Adolescents require more cautious dose escalation compared to adults 1

Special Populations Requiring Dose Reduction

Elderly patients, those with hepatic impairment, and patients with severe renal impairment require lower dosing:

• Recommended dose: 10 mg daily maximum for elderly patients and those with hepatic impairment 1
• The American Family Physician recommends starting elderly patients at approximately 50% of the adult starting dose (suggesting 5 mg initial dose) due to greater risk of adverse drug reactions 3
• No adjustment needed for mild to moderate renal impairment 1
• Use with caution in severe renal impairment 1

Pre-Treatment Screening

Screen all patients for personal or family history of bipolar disorder, mania, or hypomania before initiating escitalopram 1. This is critical to avoid precipitating manic episodes in undiagnosed bipolar disorder.

Maintenance Treatment Duration

• Continue treatment for 4-12 months after remission for first episode of major depression 3
• Longer maintenance treatment is beneficial for recurrent depression 3
• Systematic evaluation demonstrated benefit of maintenance treatment at 10-20 mg daily in adults who responded during acute treatment 1
• Periodically reassess the need for continued treatment 1

Discontinuation Protocol

Taper gradually rather than stopping abruptly to minimize discontinuation symptoms 1:

• Monitor for discontinuation symptoms including irritability, agitation, dizziness, sensory disturbances, anxiety, confusion, headache, lethargy, emotional lability, insomnia, and hypomania 1
• If intolerable symptoms occur during taper, resume the previous dose and decrease more gradually 1
• Taper over 10-14 days minimum to limit withdrawal symptoms 4

MAOI Interactions - Critical Safety Consideration

Wait at least 14 days between discontinuing an MAOI and starting escitalopram, and vice versa 1. This is essential to prevent serotonin syndrome, a potentially fatal condition.

Pharmacokinetic Considerations

• Steady-state achieved in 7-10 days 5
• Half-life: 27-33 hours, supporting once-daily dosing 5
• Peak plasma concentration: 3-4 hours after administration 5
• Linear and dose-proportional pharmacokinetics in the 10-30 mg/day range 5
• Low protein binding (56%) reduces drug interaction risk 5

Common Pitfalls to Avoid

• Do not increase dose too rapidly: Wait the full minimum period (1 week for adults, 3 weeks for adolescents) before escalating 1
• Do not use standard adult doses in elderly patients: Start lower and titrate cautiously 3, 1
• Do not abruptly discontinue: Always taper to minimize withdrawal symptoms 1
• Do not combine with MAOIs: Ensure adequate washout period 1
• Do not assume higher doses are always better: 10 mg is often sufficient, particularly for moderate depression 2

Dose Optimization Based on Severity

Research indicates severity-based dosing may optimize outcomes 2:

• Moderate depression (MADRS 22-29): 10 mg daily is optimal, with response seen at 2 weeks 2
• Severe depression (MADRS ≥30): 20 mg daily may be needed, with response typically at 4 weeks 2

While doses up to 50 mg have been studied in treatment-resistant cases, this is off-label and tolerability declines above 40 mg 6.