Pharmacokinetics of mecillinam after a single intravenous dose in patients with impaired renal function.

Twelve male patients with impaired renal function and six healthy male volunteers were given a single i.v. dose of mecillinam (400 mg). Serum concentrations of mecillinam were determined by a microbiological assay. The pharmacokinetic parameters were obtained using an open, two-compartment model. Results showed that the median elimination t 1/2 (beta) of mecillinam was longer in patients (5 h) than in volunteers (3.4 h) (p less than 0.1). The median AUC0----infinity was greater in patients (72.44 micrograms ml-1.) than in volunteers (32.96 micrograms ml-1 X h) (p less than 0.001). Moreover, the median clearance was decreased in patients (5.5 L h-1) as compared with volunteers (12.17 L h-1) (p less than 0.001). Thus the study showed prolonged half-life and decreased elimination of mecillinam in patients with impaired renal function.