In this open-label, single-center, pharmacokinetic study of repaglinide, 12 healthy volunteers (6 men, 6 women) were enrolled in each of 2 groups (total, 24 volunteers). One group consisted of young adult subjects (18 to 40 years), and the other group consisted of elderly subjects (greater than or equal to 65 years). On day 1, after a 10-hour fast, all 24 subjects received a single 2-mg dose of repaglinide. Starting on day 2 and continuing for 7 days, subjects received a 2-mg dose of repaglinide 15 minutes before each of 3 meals. On day 9, subjects received a single 2-mg dose of repaglinide. Pharmacokinetic profiles, including area under the curve, maximum concentration (C-max), time to C-max, and half-life, were determined at completion of the single-dose and multiple-dose regimens (days 1 and 9,respectively). Trough repaglinide values were collected on days 2 through 7 to assess steady state. The single-dose and multiple-dose pharmacokinetic variables of serum repaglinide were not significantly different between young adult and elderly subjects. Repaglinide was well tolerated in both groups. Hypoglycemic events occurred in 5 young adult and 5 elderly subjects. This study demonstrates that the pharmacokinetics of repaglinide are similar in healthy young adult and elderly subjects.