Medoflucon Drug Interactions

Fluconazole increased the prothrombin time after warfarin administration by about 12%. Careful monitoring of prothrombin time in patients concomitantly receiving coumarin type anti-coagulants is recommended.
The serum half life of concomitantly administered oral sulphonylureas is prolonged by fluconazole. Concomitant administration to diabetics is recommended, but the possibility of hypoglycaemic episodes should be remembered.
Concomitant administration of multiple dose hydrochlorothiazides with fluconazole led to an increase of 40% in fluconazole plasma concentration. This should not necessitate dosage adjustment, but should be noted.
Concomitant administration with phenytoin may result in a significant increase in phenytoin levels. In such cases phenytoin levels should be monitored and the dosage of phenytoin adjusted to maintain therapeutic levels.
Concomitant administration of fluconazole and rifampicin leads to a 25% decrease in AUC and 20% decrease in half life of fluconazole. In such cases, an increase in fluconazole dose should be considered. High doses of fluconazole with combination oral contraceptives give increases in the AUC for levonorgestrel and ethinyl estradiol, but efficacy of the contraceptives is unlikely to be affected.
Fluconazole 200mg per day was found to slowly increase cyclosporin concentrations. Separately, fluconazole 100mg per day had no effect on cyclosporin levels. It is recommended that patients on concomitant fluconazole and cyclosporin have cyclosporin plasma levels monitored.
It is reported that concomitant administration of fluconazole with food, antacids or cimetidine, and following whole body irradiation does not give any clinically significant alteration to fluconazole absorption.
Concomitant administration of fluconazole and theophylline resulted in a decrease in theophylline plasma clearance. High dose theophylline patients, or those at risk from theophylline toxicity, should be closely observed for toxicity signs and therapy modified if toxicity is seen.
Concomitant administration with rifabutin can lead to elevated plasma levels of rifabutin, with the risk of uveitis, and consideration should be given to reducing rifabutin dosage to 300mg per day. Concomitant administration with terfenadine can lead to accumulation of terfenadine with the risk of cardiac arrhythmia, the two should not be used together.
Short acting benzodiazepines, eg. midazolam, when given together with fluconazole resulted in substantial increases of midazolam concentrations and psychomotor effects.
There have been reports of cardiac events, including Torsades de Pointes in patients to whom fluconazole and cisapride were given together.
Interactions exist when fluconazole is co-administered with tacrolimus, leading to increased serum levels of tacrolimus and nephrotoxicity.
The AUC of zidovudine increased significantly during coadministration with fluconazole and patients should be closely monitored for development of zidovudine related adverse reactions. The use of fluconazole in patients concurrently taking astemizole or other drugs metabolized by the cytochrome P-450 system may be associated with elevations in serum levels of these drugs.
Other specific drug interaction studies have not been reported, but the possibility of other drug-drug interactions cannot be excluded.