digoxin and urapidil

Urapidil is a selective alpha 1-adrenoceptor antagonist with central antihypertensive action which is increasingly used in the treatment of hypertension. Urapidil is readily absorbed, is subject to moderate first-pass metabolism and is eliminated primarily as metabolites of much lower antihypertensive activity than the parent drug. The influences of age, renal and hepatic disease on the disposition of urapidil are reviewed. Studies on the relationship between pharmacodynamics and pharmacokinetics show that the optimum use of urapidil in clinical practice depends on an understanding of the pharmacokinetic properties of the drug.

Topics: Adult; Aged; Aged, 80 and over; Aging; Digoxin; Drug Interactions; Half-Life; Humans; Hypertension; Kidney Diseases; Liver Diseases; Male; Middle Aged; Piperazines

In an open, randomized, two-period change-over study the effect of urapidil, an antihypertensive agent, on steady-state serum digoxin levels was investigated in 12 healthy male volunteers. The subjects were given digoxin 0.25 mg once daily for 4 days to produce a steady-state digoxin level in serum. At the end of that time the subjects received either digoxin monotherapy or digoxin and concomitant treatment with urapidil 60 mg b.d. for a further 4 days. Subsequently the treatments were changed over. The absorption characteristics Cmax and tmax of digoxin were not altered by concomitant urapidil treatment. The geometric mean and nonparametric 95% confidence limits of digoxin relative bioavailability were 97% (93%-103%). Therefore, concomitant administration of urapidil with digoxin treatments did not appear to alter the rate and extent of absorption of the glycoside.

Topics: Adult; Antihypertensive Agents; Biological Availability; Blood Pressure; Digoxin; Heart Rate; Humans; Male; Piperazines; Random Allocation