Pharmacology and chemotherapy of ampicillin--a new broad-spectrum penicillin.

The pharmacology and chemotherapy of a new penicillin, 6[D(-)-alpha-aminophenylacetamido] penicillanic acid, are described. It is non-toxic, is absorbed orally and is distributed throughout the body in a manner similar to other penicillins. It is eliminated unchanged from the body in high concentrations in the bile and urine. Almost all of the antibiotic can be accounted for in the urine and intestinal contents 2 hr after intramuscular administration but not after oral administration. It is concluded that the antibiotic is not metabolized within the body. Studies with infected animals show that it is as effective as the existing oral penicillins against Staphylococcus pyogenes Smith (penicillin sensitive), Streptococcus pyogenes Group A and Diplococcus pneumoniae. It is ineffective against penicillin-resistant Staphylococci. When tested in mice infected with the gram-negative organisms, Salmonella tryphimurium and Klebsiella pneumoniae, it was considerably more active than tetracycline and chloramphenicol.