Profile of moxifloxacin drug interactions.

We report a brief description of the interaction profile of moxifloxacin. After oral administration, the absorption of moxifloxacin was unaffected by ranitidine or by food consumption. Drugs containing multivalent cations (e.g., Mg(++), Al(+++), and Fe(++), but not Ca(++)) impaired absorption. No clinically relevant effect of moxifloxacin was seen on the pharmacokinetics of digoxin under combination steady state conditions. Also, moxifloxacin did not affect the pharmacokinetics of theophylline or vice versa. This result, plus further data proving lack of interaction with glyburide, warfarin, and oral contraceptives, confirms the absence of metabolic interactions involving the cytochrome P-450 system, as previously reported. Concomitant administration of probenecid did not affect the elimination of moxifloxacin. Moxifloxacin thus has a unique drug interaction profile that is advantageous for its safe use.