Sotalol can cause life threatening ventricular tachycardia associated with QT interval prolongation.
To minimize the risk of drug induced arrhythmia, initiate or uptitrate intravenous sotalol in a facility that can provide continuous electrocardiographic monitoring and cardiac resuscitation [see Dosage and Administration (2.3) and Warnings and Precautions (5.1)]
Do not initiate intravenous sotalol therapy if the baseline QTc is longer than 450 ms. If the QTc prolongs to 500 ms or greater, reduce the dose or discontinue.