Steady-state intravenous pharmacokinetics of pirenzepine in patients with hepatic insufficiency and combined renal- and hepatic insufficiency.

The steady-state intravenous pharmacokinetics of pirenzepine has been investigated in patients with chronic liver disease and others with combined chronic liver disease and renal insufficiency. The plasma clearance (CL) of Pirenzepine, steady-state plasma concentration Cmin(ss) and dominant half life t1/2 gamma were not significantly altered in the chronic liver disease group. In patients with renal and hepatic insufficiency, CL was reduced, t1/2 gamma was prolonged from 11.1 to 19.4 h and Cmin(ss) was elevated from 36 ng/ml to 66 ng/ml compared to healthy controls. Plasma concentrations remained in the therapeutic range and the dosage regimen was well tolerated. Adjustment of the dose of pirenzepine need be considered only in cases of severe impairment of both renal and hepatic elimination.