Can Lexapro (Escitalopram) Cause Tremors?
Yes, Lexapro (escitalopram) commonly causes tremor as a dose-related adverse effect, occurring through serotonergic mechanisms that enhance physiological tremor. 1, 2
Mechanism and Clinical Presentation
Escitalopram induces tremor primarily through two pathways:
- Enhancement of physiological tremor via central serotonergic effects, which is the most common mechanism for SSRI-induced tremors 1, 3
- Serotonin syndrome (in severe cases), where tremor appears as part of a constellation including neuromuscular symptoms such as rigidity, myoclonus, hyperreflexia, and incoordination 2
The FDA label explicitly lists tremor as a neuromuscular symptom of serotonin syndrome, which can occur with escitalopram alone or particularly when combined with other serotonergic drugs 2.
Incidence and Risk Factors
- SSRIs as a class commonly produce tremor as a dose-related adverse effect, with sweating, nervousness, and tremors reported as typical side effects 1
- Approximately 63% of patients on second-generation antidepressants experience at least one adverse effect, with tremor being commonly reported 1
- Risk factors include higher doses, polypharmacy, male gender, older age, and immediate-release preparations 4
Special Populations
Neonatal exposure: When mothers take escitalopram during the third trimester, neonates can develop withdrawal symptoms including tremors, irritability, jitteriness, hypertonia, and feeding difficulties, with onset ranging from hours to days after birth and typically resolving within 1-4 weeks 5, 6
Management Approach
When tremor occurs with escitalopram:
- Dose reduction or slower up-titration should be considered, particularly if tremor appears early in treatment or with dose increases 1
- Distinguish between benign drug-induced tremor and serotonin syndrome, which requires immediate hospitalization and discontinuation of all serotonergic agents 1
- Avoid combining multiple serotonergic drugs without careful monitoring; if combination is necessary, start the second agent at low dose with particular vigilance in the first 24-48 hours after dosage changes 1
Critical Warning Signs of Serotonin Syndrome
Monitor for mental status changes (agitation, hallucinations, delirium), autonomic instability (tachycardia, labile blood pressure, hyperthermia), and neuromuscular symptoms beyond simple tremor (rigidity, myoclonus, hyperreflexia) 2. If serotonin syndrome is suspected, discontinue escitalopram immediately and initiate supportive treatment 2.
Common Pitfall
Failing to recognize that tremor is a common, expected adverse effect of SSRIs leads to unnecessary diagnostic workup 1. However, the opposite error—dismissing tremor as benign when it represents evolving serotonin syndrome—can be life-threatening 1, 2.