Cimetidine dosage regimen for patients with renal failure and for geriatric patients.

Using a recently developed computer program based on a correlation between methods to predict the elimination half-life and apparent volume of distribution of cimetidine and actual data from patients, ideal dosage regimens were generated for patients with renal impairment and for geriatric patients, together with the corresponding maximum and minimum steady state concentrations. Using the ideal dosage regimens, practical regimens with feasible dosing intervals of 6, 8 and 12 h were computed, which should result in therapeutic concentrations of 0.4 to 1.3 micrograms/ml. For uraemic patients and geriatric patients above the age of 75 years it would be desirable to have an additional oral 100 mg dosage form.