Moloxin Drug Interactions

Interactions with medicinal products: An additive effect on QT interval prolongation of moxifloxacin and other medicinal products that may prolong the QTc interval cannot be excluded. This might lead to an increased risk of ventricular arrhythmias, including torsade de pointes. Therefore, co-administration of moxifloxacin with any of the following medicinal products is contraindicated (see Contraindications): anti-arrhythmics class IA (e.g. quinidine, hydroquinidine, disopyramide); anti-arrhythmics class III (e.g. amiodarone, sotalol, dofetilide, ibutilide); antipsychotics (e.g. phenothiazines, pimozide, sertindole, haloperidol, sultopride); tricyclic antidepressive agents; certain antimicrobial agents (saquinavir, sparfloxacin, erythromycin IV, pentamidine, antimalarials particularly halofantrine); certain antihistaminics (terfenadine, astemizole, mizolastine); others (cisapride, vincamine IV, bepridil, diphemanil).
Moxifloxacin should be used with caution in patients who are taking medication that can reduce potassium levels (e.g. loop and thiazide-type diuretics, laxatives and enemas [high doses], corticosteroids, amphotericin B) or medication that is associated with clinically significant bradycardia.
Concomitant ingestion of moxifloxacin together with antacids, minerals and multi-vitamins may result in impaired absorption of the drug due to formation of chelate complexes with the multi-valent cations contained in these preparations. This may lead to plasma concentrations considerably lower than desired. Hence, an interval of at least 4 hours before and 2 hours after should be given between administration of agents containing bivalent or trivalent cations (e.g. antacids containing magnesium or aluminium, didanosine tablets, sucralfate and agents containing iron or zinc) and administration of moxifloxacin.
Concomitant administration of charcoal with an oral dose of 400 mg moxifloxacin led to a pronounced prevention of drug absorption and a reduced systemic availability of the drug by more than 80%. Therefore, the concomitant use of these two drugs is not recommended (except for overdose cases, see also Overdosage).
After repeated dosing in healthy volunteers, moxifloxacin increased Cmax of digoxin by approximately 30% without affecting AUC or trough levels. No precaution is required for use with digoxin.
Changes in INR: A large number of cases showing an increase in oral anticoagulant activity have been reported in patients receiving antibacterial agents, especially fluoroquinolones, macrolides, tetracyclines, cotrimoxazole and some cephalosporins. The infectious and inflammatory conditions, age and general status of the patient appear to be risk factors. Under these circumstances, it is difficult to evaluate whether the infection or the treatment caused the INR (international normalised ratio) disorder. A precautionary measure would be to more frequently monitor the INR. If necessary, the oral anticoagulant dosage should be adjusted as appropriate.
Clinical studies have shown no interactions following concomitant administration of moxifloxacin with: ranitidine, probenecid, oral contraceptives, calcium supplements, morphine administered parenterally, theophylline, cyclosporine or itraconazole, atenolol and glibenclamide. No dose adjustment is necessary for these drugs.
Interaction with food: Moxifloxacin has no clinically relevant interaction with food including dairy products.