Beware of QT Prolonging Drugs

From a AHA presentation
Nearly 40% of a large series of patients with a known preexisting long QT interval received an order for a QT-prolonging medication while hospitalized, thereby increasing their risk for sudden cardiac death.

Further, at-risk patients rarely underwent monitoring for further widening of the QT interval. Indeed, 8% had an ECG within 48 hours after starting the new QT-prolonging medication, Dr. Ravi K. Mareedu reported ...

Antiarrhythmic agents accounted for more than half of all prescriptions for QT prolonging medications, with amiodarone leading the way. Another 30% were for haloperidol. There were 115 orders for erythromycin and other QT-prolonging antimicrobials, 82 for methadone, and 97 orders for chlorpromazine and other antinausea drugs