Levels of carbenicillin, ticarcillin, cephalothin, cefazolin, cefamandole, gentamicin, tobramycin, and amikacin in human serum and interstitial fluid.

The ability of eight antibiotics (carbenicillin, ticarcillin, cefamandole, cephalothin, cefazolin, gentamicin, tobramycin, and amikacin) to enter human interstitial fluid was evaluated by the skin window technique. All of the antibiotics tested, except cefazolin, which has the highest percentage of protein binding, diffused into the interstitial fluid quite well. This study confirms our previous observation on the effect of high-percentage protein binding on diffusion of a drug into the minimally inflamed extravascular space.