Cefalonium is a first-generation cephalosporin antibiotic used primarily in veterinary medicine, especially in the treatment of mastitis in lactating cows. It is effective against a range of Gram-positive bacteria, including Staphylococcus and Streptococcus species, which are common causes of bovine mastitis. Administered via intramammary infusion, it delivers high concentrations directly to the infected udder quarter, ensuring targeted action and minimal systemic exposure. Its formulation allows for rapid onset of action and sustained therapeutic levels during the critical period of infection. Due to its limited systemic absorption, it is not typically used for other types of infections or in humans.