Changes in pharmacokinetics and in effect of furosemide in the elderly

In this paper the general changes in the pharmacokinetics of drugs in the elderly are summarized. The suggestion is proposed, that in the case of diuretics--which act after renal excretion--the results of these changes are totally different: contrary to other drugs the standard dose of a diuretic must have less saliuretic effect instead of more effect. This thesis is supported by the results of experiments with furosemide in old patients: the kinetics are changed as expected, leading to higher plasma levels and increased Area Under the (plasma level versus time) Curve (AUC), but the effects are--dependent on renal function--decreased. To a certain degree kinetics and dynamics of furosemide can be explained and predicted on the basis of simple patient parameters. If diuretics are used in old people to treat congestive heart failure, the normal adult dose has to be used, and occasionally a larger dose has to be given.