Live clinically-healthy non-pregnant, lactating cows were each given paromomycin in dose of 10 mg/kg body weight, by the intravenous and intramuscular routes. The serial serum samples collected after each treatment were analysed for paromomycin concentration by the microbio logical assay method using B.subltis (ATCC 6633) as test organism. A two compartment pharmacokinetic model was developed to describe the disposition of this drug. The elimination half-lifes were 5.47+0.57 and 2.55+0.12 hours for intramuscular and intravenous administration, respectively.
The apparent specific volume of distribution were more than 1 litre/kg (1.418 litre/kg) which indicates a relatively higher distribution of paro momycin to tissues than in plasma in cows. The bioavailability of paro momycin after intramuscular injection amounted to 79.93+2.53% with a maximum serum concentration (C ) of 7.44+0.23 ug/ml. about 1.5 hours after administration.