Methadone-induced torsade de pointes in a patient with normal baseline QT interval.

Torsade de pointes (TdP) is a life threatening cardiac arrhythmia that is typically associated with prolongation of the QT interval. A wide variety of nonantiarrthymic medications may trigger TdP in patients with prolonged QT interval, only a few reports have described an association between TdP and methadone. We report a case of TdP caused by a large dose of methadone in a patient with presumably normal QT interval at baseline prior to his presentation at the hospital.