What is the treatment protocol for an escitalopram (Lexapro) overdose?

Treatment Protocol for Escitalopram Overdose

Escitalopram overdose requires immediate supportive care with prolonged cardiac monitoring, gastrointestinal decontamination with activated charcoal if presenting early, and aggressive management of seizures, arrhythmias, and serotonin syndrome when they occur. 1

Immediate Assessment and Monitoring

Cardiac Monitoring Requirements

• Prolonged cardiac monitoring is mandatory due to significant arrhythmia risk, including QRS and QTc interval prolongation, wide complex tachyarrhythmias, and torsades de pointes. 1
• Monitor for at least 48-72 hours after ingestion, as QTc prolongation can be delayed and persist for days. 2
• Serial ECGs should be obtained: on admission, at 18-24 hours, and every 24 hours until QTc normalizes (typically requires >71 hours). 2

Clinical Manifestations to Monitor

• Seizures (may be delayed), altered mental status including coma 1
• Cardiovascular toxicity including QTc prolongation (>500 ms common in overdose), torsades de pointes 1, 3
• Hypertension most commonly, though hypotension can occur with co-ingestants 1
• Serotonin syndrome: hyperthermia (>40°C), increased muscle tone, autonomic dysregulation, altered mental status 3
• Drowsiness, tachycardia, and decreased consciousness are frequently reported 4

Gastrointestinal Decontamination

Activated charcoal should be considered in patients presenting early after overdose. 1

• Administer if patient presents within 1-2 hours of ingestion and can protect their airway 5
• The risk of SSRI-induced loss of consciousness or seizures is relatively small, making oral activated charcoal feasible 5
• Do not induce emesis 5

Specific Management Interventions

For Seizures

Administer intravenous benzodiazepines for seizure activity. 5

• Seizures occurred in 15% of cases in one series and can be delayed 4
• Seizure precautions and intensive care unit admission are recommended for citalopram/escitalopram-intoxicated patients 4

For Serotonin Syndrome

Treat with benzodiazepines, external cooling measures for hyperthermia (>40°C), and cyproheptadine. 5, 3

• Serotonin syndrome occurs in 14-16% of SSRI overdoses 6
• Signs include tremor, diarrhea, delirium, neuromuscular rigidity, and hyperthermia 6
• Cyproheptadine dosing: 12 mg initially, then 2 mg every 2 hours until response (maximum 32 mg/day) 3

For Cardiac Arrhythmias

• Torsades de pointes requires standard ACLS protocols including magnesium sulfate and overdrive pacing 3
• Avoid QT-prolonging medications during treatment 2
• Correct electrolyte abnormalities, particularly potassium and magnesium 2

Disposition and Observation

Emergency Department Referral Criteria

Any patient with suicidal intent, intentional overdose, or symptoms beyond mild effects (vomiting, mild somnolence, mydriasis, diaphoresis) requires emergency department evaluation. 5

Home Observation (Rare, Unintentional Only)

• Only asymptomatic patients with unintentional ingestions of up to 5 times a single therapeutic dose (50 mg for escitalopram) can be observed at home 5
• Requires poison center follow-up calls during first 8 hours 5
• This does NOT apply to intentional overdoses, which require ED evaluation regardless of dose 5

Hospital Admission

• Intensive care unit admission with continuous cardiac monitoring is recommended for all intentional escitalopram overdoses 4
• Median hospital stay is 3 days (range 1-8 days) 4
• Severity is primarily driven by neurologic and respiratory effects 4

Poison Center Consultation

Contact a poison center (1-800-221-2222) or medical toxicologist for overdosage management recommendations. 1

Critical Pitfalls

• Delayed presentation significantly worsens outcomes—cardiovascular and neurologic toxicity can be delayed by hours 3
• Elimination half-life is prolonged in overdose and does not follow normal pharmacokinetics 4
• Therapeutic serum concentrations are 15-80 ng/mL; toxic concentrations can exceed 7,300 ng/mL in fatal cases 6, 3
• Fatalities have occurred with massive ingestions (>600 mg), presenting with cardiac arrest, torsades de pointes, and refractory serotonin syndrome 3, 4
• Most patients recover fully, but high-dose ingestions (>300 mg) require aggressive monitoring and supportive care 7, 4