COMBINED USE OF ASTEMIZOLE AND KETOCONAZOLE RESULTING IN TORSADE-DE-POINTES

Torsade de pointes is a serious ventricular arrhythmia which is usuall y associated with a long QT interval. It is important to recognize the possible predisposing factors for the management of this arrhythmia. Prolongation of the QT interval and torsade de pointes has been report ed in patients with an overdose of astemizole. We report on a 63-year- old woman presenting with torsade de pointes torsade de pointes and a long QT interval caused by the combined use of astemizole (at recommen ded dosage), and ketoconazole. After discontinuation of these drugs an d treatment with a temporary pacemaker, magnesium sulfate and lidocain e, the arrhythmia was no longer observed and she was discharged in goo d condition with a normal electrocardiogram. This case should alert cl inicians to the possibility of torsade de pointes with the combined us e of astemizole and ketoconazole.