Pharmacokinetics of nifedipine after oral administration in chronic liver disease.

Presented are the results of a study in which ten healthy subjects and seven patients with hepatic cirrhosis were given 10 mg nifedipine orally; plasma concentrations of the drug were measured over 24 hours. The drug was also administered intravenously, but those results were unsatisfactory for presentation. The rate of absorption and peak plasma concentrations were similar in the two groups. There was a fourfold increase in the elimination half-life (434 +/- 74 minutes in the cirrhotics compared with 102 +/- 11 minutes in the healthy subjects). A twofold increase in the area under the plasma concentration-time curve occurred in the cirrhotic group. The study confirmed that there is clinically significant alteration in the kinetics of nifedipine in patients who have hepatic cirrhosis and that there is considerable risk of accumulation. No adverse effects were observed despite high plasma levels of nifedipine.