The pharmacokinetics of cefadroxil associated with probenecid.

The effects of probenecid on the pharmacokinetic parameters of cefadroxil administered in a single dose of 500 mg are studied. The serum and urine levels of the antibiotic were determined by a microbiologic plate diffusion method. The antibiotic follows a single-compartment model. The half-life of cefadroxil in serum has an average value of 1.13 h, rising to 1.63 h when the antibiotic is associated with probenecid. The apparent distribution volume remains unmodified with a value close to 23 liters. The lag time is 0.25 h in the absence of probenecid, rising to 1.029 h in the presence of the uricosuric agent.