Chlorpropamide and glibenclamide serum concentrations in hospitalized patients.

The relationships between the daily doses of the drugs and the steady state serum concentration was studied in 51 patients on chlorpropamide and in 27 patients on glibenclamide. All the patients were hospitalized during the study. A wide interindividual variation in chlorpropamide levels was observed and thus, the prediction of drug concentration was difficult from the dosage alone, despite a statistically significant correlation between the dose per body weight and the serum drug level. The differences could not be explained on the serum creatinine levels, age, sex, liver diseases or other drugs used concomitantly. In the case of glibenclamide, a wide interindividual variation in serum concentration of the drug also occurred.