Bioavailability and Antihyperglycemic Effect of Four Glibenclamide Tablets: A Comparative Study

Abstract

This study compared the bioavailability and antihyperglycemic effect of 5 mg glibenclamide tablets available in Sudan. Nine healthy subjects were given a 5 mg dose of either micronized glibenclamide tablets (Euglucon®) or conventional non-micronized glibenclamide tablets (locally manufactured items). Blood samples were collected at 0, 1, 2, 3, 4, 5, 6, 7, and 8 hours and analyzed for glucose concentrations. The maximum mean serum concentration of the drug (Cmax) and the mean time to maximum serum concentration (Tmax) were calculated, and the area under the concentration versus time curve (AUC) and the drug clearance (Cl) were also recorded. The mean glucose concentration was also determined in different time intervals. The results show no significant difference in the mean Tmax between the tested items. However, the mean Cmax is significantly higher (p 0.001) when the non-micronized tablets are taken (456 ng/mL) rather than the micronized tablets (291 ng/mL). Similarly, the mean AUC0-8h is significantly higher (p 0.001) with the non-micronized tablets (1915 ng/mL.h) than with the micronized tablets (1163 ng/mL.h). After 8 hours, the subjects in the micronized group had a drug clearance of 0.0430 L/Kg.h, and a clearance of 0.0260 L/Kg.h was recorded in the unmicronized group. Both tablets lower the mean glucose concentrations of the nine volunteers after 8 hours, 99 mg/dL for micronized tablets and 98 mg/dL for non-micronized tablets. Overall, the non-micronized glibenclamide tablet used in this study similarly lowered the glucose concentrations in healthy volunteer subjects to that of imported micronized glibenclamide tablets.