[Study on transfer of ceftriaxone into female genital organs]

One gram of ceftriaxone (Ro 13-9904, CTRX), a new cephalosporin antibiotic, was given intravenously to a total of 25 patients prior to abdominal total hysterectomy for uterine myoma with or without small benign ovarian tumor. Bilateral uterine arteries were clamped at 0.5, 1, 2, 6, 12 and 24 hours after administration, and serum samples and uterine tissues were taken for the measurement of CTRX concentration by bioassay method. A little difference was found in the serum concentration between cubital venous and uterine arterial serum, the half-lives being 8.0 and 7.9 hours, respectively. The initial concentrations were estimated to be 153 micrograms/ml and 160 micrograms/ml, respectively. The tissue peak concentrations were obtained at 30 minutes in the myometrium, portio vaginalis, oviduct and ovary, and at 1 hour in the endometrium and cervix uteri. These were 41, 51, 51, 39, 42 and 47 micrograms/g, respectively. The tissue concentrations after peak decreased in the same manner as the serum concentrations. Judging from its favorable transfer into the uterine tissues, CTRX was evaluated to be clinically useful in the treatment of obstetrical and gynecological infections.