An effect of fosfomycin on the pharmacokinetics of amikacin.

The effect on amikacin pharmacokinetics by fosfomycin previously or simultaneously administered via the intraperitoneal, intramuscular, or oral route was studied in the rats. Absorption of amikacin from the peritoneal cavity was prolonged by co-administered fosfomycin. High serum fosfomycin levels prevented renal lysosomal accumulation of amikacin, possibly because of the interference of urinary fosfomycin with the endocytosis of proximal tubular cells. These characteristics may explain the effect of fosfomycin in protecting against amikacin nephrotoxicity.