Beta-hemolytic streptococci A, C and G are susceptible to cloxacillin

Staphylococcus aureus and beta-hemolytic streptococci of groups A, C or G are the most common pathogens in skin infections e.g. erysipelas (1). Co-infection of these beta-hemolytic streptococci with S. aureus is often treated with the combination of penicillin and an isoxazoyl penicillin (2). Single treatment with an isoxazoyl penicillin would be easier and save antibiotics if there was sufficient activity against the beta-hemolytic streptococci groups A, C and G.