Glipizide-GITS does not increase the hypoglycemic effect of mild exercise during fasting in NIDDM

OBJECTIVE - This study compared the effect of mild exercise while fasting on plasma glucose concentrations in subjects with NIDDM treated with extended-release glipizide and subjects not taking an oral hypoglycemic agent. RESEARCH DESIGN AND METHODS - Twenty-five moderately obese subjects with NIDDM were randomized to treatment with extended-release glipizide or placebo. After 9 weeks of treatment, they fasted overnight, took their study drug, omitted breakfast, and exercised on a treadmill for 90 min. Glucose, insulin, and C-peptide concentrations were measured before, during, and after exercise. RESULTS - On the fasting-exercise day, fasting glucose concentrations were lower (153 vs. 241 mg/dl, P < 0.01) and insulin and C-peptide concentrations higher in the extended-release glipizide group. The decrement of glucose from the fasting baseline was modest and equivalent in the two groups: 17 vs. 21 mg/dl at the end of exercise and 28 vs. 27 mg/dl after 2 h of recovery. No subject had hypoglycemic symptoms. CONCLUSIONS - Chronic use of extended-release glipizide does not enhance the hypoglycemic effect of fasting plus mild exercise for people with NIDDM. Routine lifestyle treatments for NIDDM may be continued during ongoing use of this agent.