Interaction Studies of Ciprofloxacin and Metformin in Type 11 Diabetic Patients

Abstract

Metformin is mostly prescribed with ciprofloxacin in the treatment of diabetic disease with infections. However, the effect of this drug on the pharmacokinetic profile of metformin is yet to be established. The study was aimed at investigating the influence of ciprofloxacin when co-administered with metformin to freshly diagnosed patients. It is a one-way single dose cross-over study in two phases. The subjects acted as their control, and each phase was preceded by an overnight fast. In phase one, metformin was administered to all the diabetic patients, while in phase two metformin was co-administered with 500 mg ciprofloxacin. Plasma glucose levels were determined using the standard glucose oxidase method. Blood samples were collected at 0, 0.5, 1.5, 3.0, 4.0, 6.0, 8.0 and 24 h post-drug administration and stored at – 4 ?C before analysis. Plasma was obtained from the blood and the drug was extracted from the plasma using three times its volume of acetonitrile. The samples were analyzed for metformin using a reversed phase. The Ka, Cmx t1/2 and AUC of metformin when administered alone were 0.46 ±0.04 h-1, 1.14 ±0.52 ?g/ml, AUC 4.39 h?g/ml/h respectively, When co-admistered with ciprofloxacin Ka increased to 0.68 ± 0.04 h-1, Cmax to 1.43 ± 0.35 ?g/ml; while AUC and t1/2? increased to 5.72 ± 0.02 ?gh/ml and 6.8 ± 0.02 h, respectively. These increments were found to be significant (p < 0.05).Our findings showed that metformin may be co-administered with ciprofloxacin to Type 2 diabetic Patients with cautions to avoid the possible risk of toxicity or therapeutic failure.