Drug-drug interaction between voriconazole and oral hypoglycemic agents in diabetic rats

Objective: The objective was to study the of drug-drug interaction between voriconazole and oral hypoglycemic agents in normal and alloxan induced diabetic rats. Materials and Methods: The study was designed in two phases. In the first phase, influence of glibenclamide (0.45 mg/kg, p.o.) and pioglitazone (2.7 mg/kg, p.o. once daily) on blood glucose levels in normoglycemic rats was studied and then influence of voriconazole (18 mg/kg, p.o. twice daily.) pre-treatment on the hypoglycemic activity studied. Simultaneously the influence of voriconazole treatment for seven consecutive days (per se effect) on blood glucose levels was also studied in normoglycemic rats. In the second phase of the study alloxan-induced diabetic rats were used to find out the influence of voriconazole pre-treatment on glibenclamide and pioglitazone induced hypoglycemic effect in pathophysiological condition. Blood samples were collected from retro orbital plexus at regular intervals of 0.0, 0.5, 1.0, 2.0, 4.0, 8.0, 12.0, 18.0 and 24.0 h after drug treatment. All the blood samples were analyzed for plasma glucose by glucose oxidase peroxidase method (GOD/POD). Results: The therapeutic dose of voriconazole potentiates the hypoglycemic activity of glibenclamide and pioglitazone both in normoglycemic and diabetic rats respectively. Conclusion: The results indicate that the dose of oral hypoglycemic agents needs to be adjusted if co-administered with voriconazole.