Tricyclic antidepressant toxicity

Overview


Plain-Language Overview

Tricyclic antidepressant toxicity occurs when someone takes too much of a certain type of medication used to treat depression and other mental health conditions. These drugs affect the nervous system and can cause serious problems with the heart and brain. Symptoms often include confusion, drowsiness, and a fast or irregular heartbeat. The toxicity can also lead to dangerous breathing difficulties and seizures. This condition is a medical emergency because it can quickly worsen and affect vital body functions.

Clinical Definition

Tricyclic antidepressant toxicity is a clinical syndrome caused by overdose or accumulation of tricyclic antidepressants, which block norepinephrine and serotonin reuptake and have anticholinergic, quinidine-like sodium channel blocking, and alpha-1 adrenergic blocking effects. The core pathology involves cardiac conduction abnormalities (e.g., prolonged QRS), central nervous system depression, and anticholinergic toxicity. It commonly results from intentional or accidental overdose. The major clinical significance lies in its potential to cause life-threatening arrhythmias, seizures, and hypotension. Early recognition and management are critical to prevent fatal outcomes.

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Artificial Intelligence Use: Portions of this site’s content were generated or assisted by AI and reviewed by Erik Romano, MD; however, errors or omissions may occur.

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