[Effect of rokitamycin on bacterial flora in human feces]

Rokitamycin, a newly developed macrolide antibiotic was orally administered to 7 healthy male volunteers (22-25 years) for 7 consecutive days to study changes in bacterial flora and concentrations of the drug in feces, and to observe adverse reactions and laboratory test parameters. A dose of 200 mg (2 tablets: 100 mg/tablet) was given 3 times daily before meals and the fecal studies were done on the 5 days before administration (adm.) [b.a.], at the time of administration (0), and the 3rd, 5th, 7th (the final day of treatment) days during adm. [u.a.] and the 3rd, 5th, 10th, 20th, 30th days after adm. [a.a.]. The results obtained are summarized as follows. 1. Obvious changes in mean populations of total aerobes and enterobacteriaceae were not found. In changes of each bacteria of enterobacteriaceae, Escherichia coli was not observed in cases from initial day of treatment to the 3rd day a.a. Cases from which Citrobacter sp. was isolated tended to increase after 3 days u.a. and gradually decrease after 3 days a.a. Among Gram-negative bacilli, cases where isolation of Pseudomonas sp. was observed increased temporarily on the 3rd u.a., Gram-positive cocci did not show particular patterns of changes. No changes in mean count of total anaerobes were observed during the course of the experiment. Among individual anaerobes, numbers of Lactobacillus and Peptococcaceae decreased slightly from the 3rd day u.a. and returned on the 5th day a.a. 2. Clostridium difficile D-1 toxin was detected in feces at amounts approximately 500 ng/g in 2 cases each on 20th and 30th day a.a., with 1 incidence occurring in the same person on the 2 separate days. 3. The drug was detected in all 7 cases on the 3rd, 5th and 7th days u.a., and in 1 cases each on the 5th and the 30th day a.a. The mean peak level was 315.5 micrograms/g on the 7th day u.a. The reason for the detection of the drug in feces in 1 case on the 30th day a.a. at a value of 5.90 micrograms/g was not clear. 4. Adverse reactions and abnormal laboratory test results due to this drug were not observed in any cases.