Amikacin plasmatic disposition in goats, after intramuscular single dose

Amikacin is a semi-synthetic antimicrobial agent belonging to the aminoglyc oside group. The main objective of the present study was to describe the ph armacokinetic behaviour of amikacin in goats, in order to obtain data for a correct intramuscular dosage thus, a 5 mg/kg intramuscular administration of amikacin was given. Amikacin plasma levels were determined by microbiolo gical method, using Bacillus subtilis EGA as the microorganism test. Blood samples were taken at 5, 10, 15, 20, 25, 30 minutes and at 1, 2, 3, 4, 6, 8 , 10 and 12 hours following the administration of the drug. The results wer e adjusted to a one compartment open model for statistical analysis. The pl asma pharmacokinetic parameters obtained were: Amikacin average plasma leve l (Cp max) of 29.7 +/- 5.1 mug/ml at 32.4 minutes. The elimination half-lif e (t(1/2)) and total body clearance (Cl/f) were 3.09 +/- 0.6 h and 0.66 +/- 0.1 ml/min/kg, respectively. The distribution volume (V-d/f) of 0.162 +/- 0.03 L/kg indicates the restricted tisular diffusion. The drug was quickly absorbed from the injection site, reaching effective concentrations that ov ercome the minimum inhibitory concentration (MIC) at least for 10 hours, fo r most of the pathogens of veterinary interest. Intramuscular administratio n of 4-5 mg/kg can be considered satisfactory for the treatment of patholog ies produced by these microorganisms.