Case Report: Severe SIADH and QTc prolongation induced by escitalopram-quetiapine interaction in a CYP2C19 intermediate metabolizer at therapeutic doses
Journal: Frontiers in Pharmacology
Year: 2026

Escitalopram is widely regarded as a well-tolerated selective serotonin reuptake inhibitor (SSRI) with a favorable safety profile. However, severe adverse events can occur even at therapeutic doses in susceptible individuals. Here, we report a rare case of simultaneous life-threatening Syndrome of Inappropriate Antidiuretic Hormone secretion (SIADH) and cardiac toxicity induced by standard-dose escitalopram. A 51-year-old female (weight 50 kg) presented with severe fatigue and anorexia. Initial