Serum and tissue concentrations of Ceftriaxone, a new cephem antibiotic.

Studies of Ceftriaxone (CTRX), a new broad spectrum semisynthetic cephem antibiotic fed to the following conclusion:The serum level of CTRX in 3 healthy adults given 500mg reached a maximum of 96.3μg/ml 15 minutes after intravenous injection and a clinically effective serum CTRX level of 27.3μg/ml was still demonstrable 8 hours later. The tissue concentration of CTRX was 7.5μg/g in human palatine tonsils and 7.1μg/g in the mucous membrane of the maxillary sinus one hour after intravenous injection, when the serum level was 66.3μg/ml and 67.4μg/ml, respectively.These concentrations are higher than those other cephem antibiotics after intravenous injection of 500mg.