Pharmacokinetic studies of metronidazole in goats

1. Pharmacokinefic studies of metronidazole in goats after single dose oral and i. v. administration at 50mg and 20 mg/kg respectively were carried out. 2. The mean blood level time profile obtained after oral administration showed maximum concentration C (max) at 2 b and the therapeutic concentration C (ther) in blood above 0.70 (g/ml persisted upto 6 h. 3. Metronidazole administered i. v. produced shorter duration of C (ther) with levels ranging from 2.29( 1.4 to 37.36( 1.5 Kg/ml till 2 h ; the drug attained C (maxI in milk at 1 b and Cm (ther) interestingly was maintained upto 12 h following i. v. administration. 4. The semilogrithmic plot of blood level time profiIe of metronidazoie administered i. v. showed biphasic decline which was suggestive of 'two compartment open model kinetics. 5. The elimination half life (t 0.5 ()and the apparent volume of distribution (V.d) were found to be 56(2.45 min and 0.93(0.96 L/kg respectively and the ratio of the microscopic rate constants (K12+K21)/K2 was also wider. 6. The extent of plasma protein bound drug ranged between 25.50 to 36.27 %