Indicated for serious infections caused by susceptible Gram-positive organisms, staphylococci (both penicillinase and non-penicillinase-producing), streptococci (except Streptococcus faecalis) and pneumococci. It is also indicated in serious infections caused by susceptible anaerobic pathogens such as Bacteroides spp., Fusobacterium spp., Propionibacterium spp., Peptostreptococcus spp., and Microaerophilic streptococci.