Additive effect w/ drugs that prolong QT interval e.g. antiarrhythmic agents (amiodarone, quinidine, sotalol), arsenic trioxide, cisapride, chlorpromazine, droperidol, mefloquine, dolasetron, mesoridazine, moxifloxacin, pimozide, tacrolimus, pentamidine, thioridazine, ziprasidone. Increased risk of blood glucose disturbances w/ drugs that alter blood glucose concentrations (e.g. antidiabetics). Systemic admin may elevate plasma concentrations of theophylline, interfere caffeine metabolism, enhance effects of oral anticoagulant (warfarin and its derivatives), and transient elevations in serum creatinine w/ ciclosporin.