Benzylpenicillin (INN, AAN, BAN), commonly known as penicillin G, (USAN) is a narrow spectrumpenicillin antibiotic that is given intravenously or intramuscularly as a treatment for syphilis,meningitis, endocarditis, pneumonia, lung abscessesand septicaemia in children.^[1] Penicillin G is typically given by injection parenterally, bypassing the intestines, because it is unstable in the highly acidic stomach. Because the drug is given parenterally, higher tissue concentrations of penicillin G can be achieved than is possible withphenoxymethylpenicillin. These higher concentrations translate to increased antibacterial activity.

It is on the World Health Organization’s List of Essential Medicines, a list of the most important medications needed in a basic health system.^[2]

(From Wikipedia, July 2015)