FLUOROQUINOLONES MAY PROLONG THE QT INTERVAL IN SOME PATIENTS. GEMIFLOXACIN SHOULD BE AVOIDED IN PATIENTS WITH A HISTORY OF PROLONGATION OF THE QTC INTERVAL, PATIENTS WITH UNCORRECTED ELETROLYTE DISORDERS (HYPOKALEMIA OR HYPOMAGNESEMIA), AND PATIENTS RECEIVING CLASS IA (E.G., QUINIDINE, PROCAINAMIDE) OR CLASS III (E.G., AMIODARONE, SOTALOL) ANTIARRHYTHMIC AGENTS.
PHARMACOKINETIC STUDIES BETWEEN GEMIFLOXACIN AND DRUGS THAT PROLONG THE QTC INTERVAL SUCH AS ERYTHROMYCIN, ANTI-PSYCHOTICS, AND TRICYCLIC ANTIDEPRESSANTS HAVE NOT BEEN PERFORMED. GEMIFLOXACIN SHOULD BE USED WITH CAUTION WHEN GIVEN CONCURRENTLY WITH THESE DRUGS, AS WELL AS IN PATIENTS WITH ONGOING PROARRHYTHMIC CONDITIONS, SUCH AS CLINICALLY SIGNIFICANT BRADYCARDIA OR ACUTE MYOCARDIAL ISCHEMIA. THE LIKELIHOOD OF QTC PROLONGATION MAY INCREASE WITH INCREASING DOSE OF THE DRUG