[Fundamental study on ceftriaxone]

Ceftriaxone (CTRX) was examined in the blood level and urinary excretion between a healthy group of 2 persons receiving 1 g CTRX for 1 day and the other of 3 patients with renal failure receiving 1 g for 3 days, both by intravenous injection or intravenous drip infusion. In the healthy group, the blood half-life time of CTRX was 6.0 hours in 1 person and 8.2 hours in the other, being 7.1 hours on average. The mean blood level in the healthy group was 199 micrograms/ml at peak and was 13 micrograms/ml at 24 hours after administration. In patients with renal failure, the peak blood level ranged from 136.8 to 161.1 micrograms/ml on the 1st day, from 163.1 to 217.0 micrograms/ml on the 2nd day and from 156.4 to 189.7 micrograms/ml on the 3rd day, showing no tendency of getting higher, while the bottom level did from 15.2 to 47.4 micrograms/ml on the 1st day, from 23.3 to 67.9 micrograms/ml on the 2nd day and from 10.9 to 72.6 micrograms/ml on the 3rd day. The urinary excretion rate was 54.6 +/- 3.7% on average in the healthy group while it ranged from 13.7 +/- 1.8 to 27.9 +/- 7.9% in the patient group. CTRX was effective especially against E. coli among the strains clinically isolated from the patients with renal failure. No side effects were observed in any case.