Evaluation of absorption and pharmacokinetic parameters of various injectable products of gentamicin in rabbits

Abstract

Gentamicin (GM) is an aminoglycoside antibiotic with a narrow therapeutic range and severe adverse effects. The relation between its serum concentration and toxicity and neprotixicity have been estabilished. It has been recommonded that its peak serum concentrations should not be exceed 12 to 15 ug/ml. For these reseans this study was undertaken to evaluate the bioavailability and pharmacokinetics characteristics of generic gentamicin l0 mg/ml (GM/G) - compared to g entamicin 40mg/ml (GM/B). Eight adult and healthy rabbits weighed 1.5. 2. 75 Kg. were given GM as a single IM injection (2. 5 mg/kg). Blood samples were collected from the ear vein and serum was separated and kept frozen prior to assay. Serum concentrations of GM were determined using enzyme multiple immunoassay technigue EMIT (syva). Pharmacokinetics parameters were calculated from the serum concentrations data with the aid of computer program. It has been found that the pharmacokinetics of GM follows a two compartmental model, and:
1 - Tl 2 elim.elimination half life, is 1. 57 h, for GM/G and 1.13 h. for GM/B. tl/2 dis, distribution half
life, is 0. 86 for GM/G and 0. 45h . for GM/B.
2 - Cp max' Peak plasm level is 7.83 mg/L for Gm/G and 8.38 mg/L for. GM/B.
3 - Tmax time to reach peak plasm level is 0.37 . for GM/G and 0. 4oh . for GM/B.
4 - Auc 4, Area under concentration - time curve to 4 hour, and Auc inf. Area under concentration. - time
curve to infnity are 10. 94, 11. 32 mgml/h for GM/G and 10.17. 10.48 mgml/h for GM/B .
Statistical analysis T. Test, has shown Theve is no significat difference between These two products and
therefore, These products are bioequivalent.