Abstract
The validity of the Giusti-Hayton method for dosage regimen adjustment in renal impairment was examined using a histamine H2-antagonist, ranitidine. Five healthy volunteers with normal renal function and 20 patients with varying degrees of renal impairment were enrolled in the study. The former received ranitidine at standard unit dose of 150 mg and the latter received doses calculated from the creatinine clearance value using the Giusti-Hayton method. Pharmacokinetic parameters were compared between healthy volunteers and patients after a single oral dose of ranitidine. As a result of dosage adjustment for each patient by the Giusti-Hayton method, the AUC0→∞ of renally impaired patients became almost comparable to those from healthy volunteers.
In conclusion, the Giusti-Hayton method was considered useful to keep the ranitidine AUC0→∞constant and, eventually, to keep mean blood levels of ranitidine in a constant steady state, irrespective of the renal function of the subject.
