Why is Lexapro (escitalopram) prescribed for a 16-year-old and what are its common side effects?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: November 28, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Why Lexapro is Prescribed for a 16-Year-Old and Common Side Effects

Lexapro (escitalopram) is prescribed for adolescents aged 16 to treat anxiety disorders—including generalized anxiety, social anxiety, separation anxiety, and panic disorder—because SSRIs like escitalopram are evidence-based first-line pharmacological treatments for these conditions in youth, often combined with cognitive behavioral therapy for optimal outcomes. 1

Why Prescribe Lexapro for Adolescents

Evidence-Based Treatment for Anxiety Disorders

  • The American Academy of Child and Adolescent Psychiatry (AACAP) recommends SSRIs as effective pharmacological treatment for anxiety disorders in patients aged 6 to 18 years, including social anxiety, generalized anxiety, separation anxiety, and panic disorder. 1
  • Combination treatment (CBT plus an SSRI) is preferentially recommended over monotherapy alone for these anxiety disorders in adolescents. 1
  • Escitalopram demonstrates robust efficacy in treating anxiety disorders and associated depressive symptoms, with clinical improvement typically beginning within 2 weeks and maximal improvement by week 12. 1

Favorable Pharmacological Profile

  • Escitalopram has the least effect on CYP450 enzymes compared to other SSRIs, resulting in lower propensity for drug-drug interactions—an important consideration for adolescents who may be taking other medications. 1
  • The medication has linear pharmacokinetics with a half-life of 27-33 hours, allowing once-daily dosing that improves adherence in adolescents. 2
  • Escitalopram is highly selective for the serotonin transporter and represents the therapeutically active S-enantiomer of citalopram, providing efficacy at lower doses. 3, 4

Common Side Effects to Educate About

Most Frequent Side Effects (Generally Mild to Moderate)

  • Nausea (most common, typically mild and transient) 1, 5
  • Insomnia or sleepiness 1, 5
  • Headache 1
  • Dizziness 1, 5
  • Dry mouth 1, 5
  • Diarrhea or constipation 1, 5
  • Sweating 1, 5
  • Fatigue or weakness 1, 5
  • Decreased appetite 5
  • Tremor 1

Adolescent-Specific Side Effects

  • Increased thirst 5
  • Abnormal increase in muscle movement or agitation 5
  • Nosebleed 5
  • Heavy menstrual periods 5
  • Possible slowed growth rate and weight changes (height and weight should be monitored during treatment) 5

Serious Side Effects Requiring Close Monitoring

Black Box Warning: Suicidal Thinking and Behavior

  • All SSRIs carry an FDA black box warning for increased suicidal thinking and behavior in patients through age 24 years. 1
  • The pooled absolute risk is 1% for youth on antidepressants versus 0.2% on placebo (number needed to harm = 143). 1
  • Close monitoring is essential, especially during the first months of treatment and following dose adjustments. 1, 5

Behavioral Activation/Agitation

  • Initial adverse effects can include anxiety, agitation, motor restlessness, insomnia, impulsiveness, or disinhibited behavior—more common in younger children than adolescents. 1
  • This typically occurs early in treatment or with dose increases, supporting the recommendation to start with a subtherapeutic "test" dose and titrate slowly. 1
  • Starting at low doses and increasing slowly (at 1-2 week intervals) helps minimize this risk. 1

Serotonin Syndrome

  • Can occur when combining escitalopram with other serotonergic drugs (including MAOIs, other SSRIs/SNRIs, tramadol, certain stimulants, dextromethorphan, St. John's Wort). 1
  • Symptoms include mental status changes (confusion, agitation), neuromuscular hyperactivity (tremors, clonus, hyperreflexia), and autonomic hyperactivity (hypertension, tachycardia, diaphoresis). 1
  • Concomitant use with MAOIs is absolutely contraindicated. 1

Other Serious Effects

  • Sexual dysfunction (though less common in adolescents than adults) 1
  • Abnormal bleeding (especially with concurrent NSAIDs or aspirin) 1
  • Hypomania or mania (rare, may appear later in treatment and persist after discontinuation) 1
  • Seizures (rare) 1

Discontinuation Syndrome

  • While escitalopram has a longer half-life than some SSRIs, discontinuation syndrome can still occur with abrupt cessation. 1
  • Symptoms include dizziness, fatigue, headaches, nausea, insomnia, sensory disturbances, anxiety, and irritability. 1
  • Never stop abruptly—taper gradually under medical supervision. 1

Critical Prescribing Considerations

Dosing Strategy

  • Start with a subtherapeutic "test" dose to assess for initial anxiety or agitation. 1
  • Increase dose slowly at 1-2 week intervals for escitalopram to optimize benefit-to-harm ratio. 1
  • Parental oversight of medication regimens is paramount in children and adolescents. 1

Monitoring Requirements

  • Close monitoring for suicidality, especially in first months and after dose changes 1, 5
  • Monitor height and weight in adolescents 5
  • Assess for behavioral activation, particularly in the first 24-48 hours after starting or dose increases 1
  • Use standardized symptom rating scales to track treatment response 1

Drug Interactions to Avoid

  • Absolute contraindication: MAOIs (must wait appropriate washout period) 1, 5
  • Exercise caution with other serotonergic drugs, QT-prolonging medications, and drugs metabolized by CYP2C19 1, 5
  • Cimetidine and omeprazole can increase escitalopram exposure, though changes are generally not clinically significant 2

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

The clinical pharmacokinetics of escitalopram.

Clinical pharmacokinetics, 2007

Research

Escitalopram.

Expert opinion on investigational drugs, 2002

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.