Bactericidal antibiotic from the group of semisynthetic penicillins, is resistant to the action of penicillinase. It blocks the synthesis of the bacterial cell wall by disrupting the late stages of peptidoglycan synthesis (prevents the formation of peptide bonds by inhibiting transpeptidase), causes lysis of fissile bacterial cells.
It is active against gram-positive microorganisms: Staphylococcus spp. (including those producing penicillinase), Streptococcus spp., incl. Streptococcus pneumoniae, Corynebacterium diphtheriae, Bacillus anthracis, anaerobic spore-forming rods, Gram-negative cocci (Neisseria gonorrhoeae, Neisseria meningitidis), Actinomyces spp., Treponema spp.
It is inactive with respect to the majority of gram-negative bacteria, rickettsia, viruses, protozoa, fungi.