Changes in muscle blood flow after smoking a cigarette determined by a new noninvasive method

Summary The pharmacokinetics of the H₂-receptor antagonist famotidine, after oral administration of a 20 mg tablet, has been studied in 10 elderly patients with normal renal function (CL_CR59 ml·min^–1, Mean=80 ml·min^–1), 5 elderly patients with renal insufficiency (CL_CR38 ml·min^–1, Mean=15 ml·min^–1), and 6 healthy young volunteers.Elimination half-life in the elderly patients with renal insufficiency was significantly prolonged compared to the elderly patients with normal renal function and the young volunteers. The correlation coefficient between creatinine clearance and the elimination rate constant of famotidine was 0.672. Mean urinary recovery of unchanged drug up to 24 h in the young volunteers was 44%. The mean renal clearance of famotidine in the young volunteers (270 ml·min^–1) was substantially greater than the creatinine clearance, 128 ml·min^–1, which suggests the possibility of tubular secretion of famotidine.