We describe acute mixed hepatitis (cholestatic and hepatocellular) in two women probably induced by cloxacillin. Viral causes, autoimmune hepatitis, biliary tree obstruction and other risk factors were excluded. After discontinuation of the drug evolution was favorable and clinical signs and hepatic laboratory tests became normal in both cases. We also review the literature about hepatotoxicity induced by anti-Staphylococci semisynthetic penicillins.