क्विनिडिन और सोटालोल का इंटरैक्शन

Class Ia antiarrhythmic drugs, such as disopyramide, quinidine, and procainamide, and other Class III drugs (for example, amiodarone) are not recommended as concomitant therapy, because of their potential for additive QTc prolongation [see Warnings and Precautions ( 5.1 )].

Additive to other QT-prolonging drugs ( 7.1 , 7.2 )

Antiarrhythmic and other QT Prolonging Drugs Withdraw other Class I or Class III antiarrhythmic agents prior to dosing with sotalol.

Proarrhythmic effects Like many other drugs (including all other Class Ia antiarrhythmics), quinidine prolongs the QT c interval, and this can lead to torsades de pointes , a life-threatening ventricular arrhythmia (see OVERDOSAGE ).

The effects (if any) of coadministration of other β-blockers on quinidine pharmacokinetics have not been adequately studied.

Coadministration of propranolol usually does not affect quinidine pharmacokinetics, but in some studies the β-blocker appeared to cause increases in the peak serum levels of quinidine, decreases in quinidine's volume of distribution, and decreases in total quinidine clearance.