Plasma and dialysate levels of pefloxacin and its metabolites in CAPD patients with peritonitis.

Six patients with acute peritonitis undergoing continuous ambulatory peritoneal dialysis for end-stage renal failure received an 800 mg loading dose of pefloxacin mesylate orally followed by 400 mg twice daily orally for 10 or 21 days. Plasma and dialysate levels of both pefloxacin and its metabolites were measured. Plasma levels in excess of the MIC for all infective bacteria were achieved within 90 min and in dialysate within 4 h. No significant accumulation of pefloxacin or its metabolite norfloxacin was noted. However, both serum and dialysate levels of the metabolite pefloxacin N-oxide rose continuously during treatment. Plasma and dialysate levels of all three agents fell rapidly during the five days after treatment had stopped. No major side effects were observed, although two patients developed Achilles tendonitis.