Abstract

We present a case of paracetamol overdose in a 34-year-old female with a history of depression and alcoholism. Following treatment with N-acetylcysteine (Parvolex®) our patient developed ventricular tachycardia resulting in cardiac arrest from which she was successfully resuscitated. Subsequent ECG demonstrated prolongation of the QTc interval and repeat blood tests revealed a significant fall in serum potassium from 4.2mmol/l on admission to 2.2mmol/l. The possible mechanisms contributing to the development of hypokalaemia after overdose with paracetamol are discussed. The existing literature relating to paracetamol-induced hypokalaemia is briefly reviewed.
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