Drug-induced torsades de pointes (TdP), a life-threatening polymorphic ventricular tachycardia associated with prolongation of the QT interval, has been the main safety reason for the withdrawal of non-cardiac agents from clinical use over the last decade. This complication is commonly referred to as drug-induced proarrhythmia. The present review highlights on the mechanisms underlying the drug-induced QT interval prolongation and TdP as well as on the identification of easily recognized risk factors that predispose to this potentially life-threatening condition.