Clinical pharmacokinetics and metabolism of pyrazinamide in healthy volunteers.

Eight healthy volunteers were treated with a single dose of pyrazinamide 35 mg/kg. The aim of the study was to evaluate the pharmacokinetic profile of the product and of its metabolites. Urine and blood samples were collected till the 60th h. The kinetics of pyrazinamide could be characterized as follows: CPmax = 50.1 micrograms/ml, tmax less than 1 h, t1/2 alpha = 3.2 h, t1/2 beta = 23 h, U(0-60 h) = 1.6% of the dose administered. The kinetics of the main metabolite, the pyrazinoic acid, gave the following values: CPmax = 66.6 micrograms/ml, tmax = 4 h, t1/2 beta = 12.3 h, U(0-60 h) = 37.5%, of the administered dose.