Kanamycin sulfate in the horse: serum, synovial fluid, peritoneal fluid, and urine concentrations after single-dose intramuscular administration.

Six healthy adult mares were given a single dose of kanamycin sulfate (200 mg/ml) IM at a dosage rate of 5 mg/kg of body weight. Kanamycin concentrations in serum, synovial fluid, peritoneal fluid, and urine were measured serially over a 48-hour period. The mean peak serum kanamycin concentration was 12.55 microgram/ml at 1 hour. Mean peak kanamycin concentrations in synovial fluid and peritoneal fluid were 7.25 microgram/ml and 9.27 microgram/ml at 2 hours and 3 hours, respectively. These concentrations decreased steadily in parallel with serum concentrations and were still measurable at 48 hours. Urine concentrations of kanamycin were relatively high, with a mean peak concentration of 80.51 microgram/ml at 1 hour.