ATCvet code: QJ51CF02
Cloxacillin, a semi-synthetic β-lactam antibiotic, is active against Gram-positive organisms, but is not destroyed by staphylococcal penicillinase. It is therefore active against penicillin resistant staphylococci which are an important cause of mastitis. The antibiotic is bactericidal at the concentrations produced in the udder and is non-irritant to the udder tissues.