Tricyclic antidepressant poisoning (emergency department diagnosis and management)

Meet the patient

A young woman is brought in drowsy after taking an unknown number of her mother's amitriptyline tablets. She is tachycardic, her skin is hot, dry and flushed, and her pupils are dilated. The first ECG shows a broad QRS.

Read the ECG before anything else. In a prospective study of 49 patients, no seizures or ventricular arrhythmias occurred with a maximal limb-lead QRS under 0.10 second, while patients at 0.10 second or longer had a 34 per cent incidence of seizures and 14 per cent of ventricular arrhythmias; ventricular arrhythmias were seen only at 0.16 second or longer, and serum drug levels failed to predict either.^[11]

References22ShowHide

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