A number of drug interactions that involve quinidine have been reported.1 These include both pharmacokinetic interactions in which plasma concentrations of other drugs, most notably digoxin, are influenced by quinidine, and pharmacologic interactions. The latter is exemplified by a recent report of marked hypotension when intravenous verapamil was given to patients receiving oral quinidine preparations.2 This hypotension was presumably due to α-adrenergic blockade and the peripheral vasodilatation was a result of both quinidine and verapamil. We report a patient with cyanotic congenital heart disease and atrial flutter with 1:1 atrioventricular conduction who had a previously unreported quinidine-verapamil pharmacokinetic interaction.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine