What are the most common side effects of Lexapro (escitalopram) in adults with depression or anxiety disorders?

Most Common Side Effects of Lexapro (Escitalopram)

The most common side effects of Lexapro in adults are nausea (15-18%), insomnia (9-12%), ejaculation disorder (9-14% in males), diarrhea (8%), fatigue (5-8%), and increased sweating, with nausea being the single most frequently reported adverse effect and the most common reason for treatment discontinuation. 1

Gastrointestinal Side Effects

The gastrointestinal system is most commonly affected by escitalopram:

• Nausea occurs in 15% of patients with depression and 18% of patients with generalized anxiety disorder, making it the most prevalent side effect across all indications 1
• Diarrhea affects 8% of patients with depression and 8% with anxiety disorders 1
• Constipation occurs in 3-5% of patients 1
• Dry mouth, indigestion, and abdominal pain each affect 2-3% of patients 1
• The American Academy of Family Physicians notes that escitalopram may be better tolerated than sertraline with lower gastrointestinal side effects 2

Clinical Pearl: Taking escitalopram with food may help reduce nausea, and these gastrointestinal symptoms typically emerge within the first 1-2 weeks of treatment 2

Psychiatric and Sleep-Related Effects

• Insomnia affects 9% of depression patients and 12% of anxiety disorder patients, making it one of the most common reasons for discontinuation 1
• Somnolence (daytime sleepiness) occurs in 6% of depression patients and 13% of anxiety patients 1
• Decreased appetite affects 3% of patients 1
• Vivid dreams and increased sweating are commonly reported 3

Important consideration: The dose-dependent nature of insomnia is notable—14% of patients on 20 mg/day experience insomnia compared to 7% on 10 mg/day 1

Sexual Dysfunction

Sexual side effects are particularly common and often underreported:

• Ejaculation disorder (primarily ejaculatory delay) occurs in 9% of males with depression and 14% of males with generalized anxiety disorder 1
• Decreased libido affects 3-7% of patients 1
• Impotence occurs in 3% of males 1
• Anorgasmia affects 2-6% of females 1

The FDA label explicitly acknowledges that these rates likely underestimate actual incidence due to patient and physician reluctance to discuss sexual problems 1

Neurological Effects

• Dizziness affects 5% of patients 1
• Headache is common (35% in some studies), though often mild 4
• Fatigue occurs in 5-8% of patients 1
• Tremor, nervousness, and bruxism have been reported 3

Dose-Dependent Effects

The 20 mg/day dose shows substantially higher rates of common side effects compared to 10 mg/day:

• Insomnia: 14% vs 7% 1
• Diarrhea: 14% vs 6% 1
• Dry mouth: 9% vs 4% 1
• Somnolence: 9% vs 4% 1
• Increased sweating: 8% vs 3% 1

The overall incidence of adverse events at 20 mg/day (86%) is notably higher than at 10 mg/day (66%) or placebo (61%) 1

Discontinuation Rates

• 6% of depression patients discontinued escitalopram due to adverse events compared to 2% on placebo 1
• 8% of generalized anxiety disorder patients discontinued treatment due to adverse events compared to 4% on placebo 1
• Nausea (2%) and ejaculation disorder (2% of males) were the specific adverse events leading to discontinuation in at least 1% of patients at twice the placebo rate 1

Serious Adverse Events to Monitor

While less common, clinicians must remain vigilant for:

• Increased suicidal thinking and behavior in patients up to age 24 years (pooled absolute risk 1% vs 0.2% with placebo) 3
• Behavioral activation (motor restlessness, insomnia, impulsiveness, aggression), particularly in younger patients early in treatment 3
• QT prolongation, though less commonly reported with escitalopram than citalopram 5, 3
• Serotonin syndrome when combined with other serotonergic medications 2

Comparative Tolerability

• Escitalopram demonstrates better overall tolerability than sertraline, with lower gastrointestinal side effects 2, 3
• Escitalopram has fewer effects on CYP450 enzymes, resulting in lower drug interaction potential compared to other SSRIs 2, 3
• Only nausea occurred in more than 10% of escitalopram-treated patients in pooled analyses 6

Pediatric Considerations

In pediatric patients (ages 6-17), the adverse event profile is generally similar to adults, with additional commonly reported effects including back pain, urinary tract infection, vomiting, and nasal congestion 1