Prolonged QTc interval due to escitalopram overdose
Reema Mohammed1, John Norton, Stephen A Geraci
1Dept. of Pediatrics, University of Mississippi Medical Center, Jackson 32916, USA.
Journal of the Mississippi State Medical Association
|March 5, 2011
Summary
Escitalopram overdose can cause QTc prolongation, a risk factor for dangerous heart arrhythmias. Careful ECG monitoring for at least two days is crucial after significant escitalopram ingestion, especially in patients with suicidal ideation.
Area of Science:
- Cardiology
- Clinical Pharmacology
- Psychiatry
Background:
- Acquired long QT syndrome is often linked to antibiotics and antidepressants.
- Escitalopram overdose causing QTc prolongation is rarely documented.
Observation:
- A case of a 33-year-old woman with a QTc prolongation of 491 ms after ingesting lithium, escitalopram, and alcohol.
- Serial ECGs revealed persistent QTc prolongation exceeding 460 ms for over 71 hours post-ingestion.
Findings:
- Escitalopram overdose can lead to significant and prolonged QTc interval prolongation.
- The patient's QTc interval normalized after more than two days of monitoring.
Implications:
- Caution is advised when prescribing escitalopram to patients with suicidal ideation.
- Prolonged ECG monitoring (≥2 days) is recommended post-escitalopram overdose to prevent life-threatening arrhythmias like torsades de pointes.
- Consider co-ingestions and individual patient factors when determining monitoring duration.
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