ATCvet code: QJ01AA06.
Pharmacotherapeutic group
Oxytetracycline is a bacteriostatic antibiotic which has broad spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. After absorption it enters most tissues and body fluids, with the exception of CSF. It is excreted unchanged, mainly in urine.
Pharmacokinetic particulars
From the site of injection, the drug is effectively and rapidly absorbed with minimal irritation of the tissue due to the low viscosity of the solvent contained in the formulation, polyvinyl pyrrolidone (PVP).
Depending on the dose rate the duration of action after a single administration is for 24 hours or prolonged to 48 – 60 hours.
After a standard dose of 3 – 8 mg oxytetracycline/kg bodyweight to target animals, drug peak plasma concentrations were achieved in 1 – 4 hours and lasted to the level of 0.5 – 1.0 µg/ml, regarded as effective, in about 24 hours; by giving intramuscular doses of 10 – 20 mg oxytetracycline/kg bodyweight the action was prolonged and concentrations exceeding 0.5 – 1.0 µg/ml were maintained for about 48 hours.
The drug is widely distributed in the body with highest concentrations in liver, spleen, kidneys and the lungs. Oxytetracycline is moderately protein bound (about 50 %) and is excreted mainly unchanged by the renal route, with same in the faeces and milk.