Clozapine is associated with a risk of myocarditis and cardiomyopathy. The exact mechanisms still remains unclear although there have been a range of proposals ranging from hypersensitivity reactions, toxic effects of the drug to vitamin deficiency. We present three cases where there were minor deviations of heart function or structure prior to the onset of clozapine treatment. One case developed a mild rise in troponin-1 levels within one month of clozapine treatment. We also review the current literature on the link between clozapine, myocarditis and cardiomyopathy and suggest clinical guidelines for monitoring patients for cardiac symptoms prior to commencing and while on clozapine treatment.
