DISOPYRAMIDE AND MACROLIDES
Case reports suggest that erythromycin increases disopyramide levels, and this has resulted in QT prolongation, cardiac arrhythmias and heart block. Similar effects have been seen when clarithromycin or azithromycin are given with disopyramide. Josamycin and telithromycin are expected to interact similarly. See also drugs that prolong the QT interval.
Some of the manufacturers of disopyramide recommend avoiding the combin- ation of disopyramide and macrolides that inhibit CYP3A, and this would certainly be prudent in situations where close monitoring is not possible.
Some of the manufacturers of disopyramide recommend avoiding the combin- ation of disopyramide and macrolides that inhibit CYP3A, and this would certainly be prudent in situations where close monitoring is not possible.