Gentamicin is an aminoglycoside antibiotic which is bactericidal by inhibiting protein synthesis in susceptible bacteria. Gentamicin is not significantly bound by animal protein and hence provides useful
concentrations in peritoneal and pleural fluids. Its clearance rates may be reduced in cases of renal impairment, and prolonged courses are considered to be potentially nephrotoxic. Gentamicin should only be used when the target bacterial species is known to be sensitive to this antibiotic.
Gentamicin is effective against a range of gram negative bacteria including: Actinobacillus sp., Klebsiella sp., Bordetella bronchiseptica, Enterobacter sp., Pseudomonas sp. and E.coli.
Gentamicin is indicated in infections in horses, dogs and cats which are known to be responsive to Gentamicin. GENTAMICIN is rapidly absorbed following parenteral administration but reaches only low concentrations in the CSF and eye. Peak serum concentrations are reached within 30 – 60 minutes after intramuscular injection. Therapeutic plasma concentrations are maintained in the horse for up to 6 hours following intramuscular injection. Gentamicin crosses the placenta. Excretion is primarily by glomerular filtration. Because of its rapid absorption after administration, and rapid bactericidal action, Gentamicin is particularly useful in acute infections, particularly of the urinary tract, reproductive tract and respiratory
DOSAGE AND ADMINISTRATION
Horses: 1.5 mg/kg every eight hours.
Mares – Intra-uterine infusion – 2.5 g, diluted in 400 mL sterile normal
saline. Infuse daily for 3 – 5 days during oestrus.
Cats and Dogs: 4.0 mg/kg twice on the first day then once daily.
Give by sterile subcutaneous, intramuscular or intravenous injection.
Administration should not exceed 5 days.
Do not use in animals with impaired renal function.
Avoid using Gentamax in small cats and dogs as there is a risk of overdosing due to the very small injection volumes required. Use only in situations where sensitivity indicates that there is no suitable
alternative antibiotic. Do not use in pregnant animals, as gentamicin crosses the placenta.
Meat Witholding Period: NOT TO BE USED in horses that may be slaughtered for human consumption.