Stability of fluconazole syrup

Abstract

Fluconazole is an azole antifungal agent which is used for systemic candidiasis. Fluconazole syrups (50 mg/5 ml) were prepared by using cosolvent technique for increasing solubility of fluconazole in water. The mixed solvent used in this preparation was 4% w/v PEG 4000,7% v/v ethanol, 7% v/v PG and 82% v/v water. The stability of fluconazole syrups, which contained various concentration of different kinds of antioxidants under the accelerated light, was studied and compared with light protecting condition at 60 ℃ throughout 107 days. It was found that all formulations changed to dark brown color according to the color change of syrup. The kinetics proceeded according to a zero order reaction. In this study the most chemically stable formulation was the fluconazole containing 0.001% w/v of propyl gall ate which was stored under light protecting condition. The shelf-life study was evalulated by accelerated testing technique at 45℃, 55℃, 65℃, 70℃ and at ambient temperature. A linear regression line was obtained from Arrhenius plot of the reaction rate (k) against reciprocal of degree kelvin (1/T). The heat of activation was found to be 13.02 kcal/mol and the estimated shelf life was 834 days.