Abstract

The pharmacokinetics of metronidazole was determined after a single intramuscular (i.m.) dose of 30 mg⋅kg-1-body weight in five camels, sheep and goats. Marked differences were found between the three species in some of the kinetic parameters. For example, the elimination half-lives (t1/2; h) in camels, sheep and goats were 10.0, 6.21 and 5.87, respectively. The drug maximum concentrations in plasma, Cmax (mg⋅ml-1), were 28.3, 54.6 and 54.4 in camels, sheep and goats, respectively. The time to reach Cmax, tmax (h), were 5, 4 and 2 in camels, sheep and goats, respectively. The mean residence times (MRT; h) in camels, sheep and goats were 16.7, 10.8 and 8.64, respectively. In the light of the present kinetic data and known microbial sensitivities of metronidazole, we recommend an i.m. dose of 15 mg⋅kg-1 in camels and 10 mg⋅kg-1 in sheep and goats, every 12 h. Ruminants, kinetics, metronidazole, antiprotozoals, antibacterials Metronidazole (2-methyl-5-nitroimidazole-1-ethanol) is a synthetic bactericidal and antiprotozoal agent that is used to treat certain urogenital diseases such as trichomoniasis, giardiasis, Balantidium coli, and intestinal and extraintestinal amoebiasis. It is also effective against bacterial anaerobes. The drug is also considered a reliable marker or probe for studying liver function in vivo (Muscar et al. 1995). The pharmacokinetics of this drug has been reported previously following intravenous (i.v.), oral or rectal administration t