Ertapenem is meropenem in which the one of the two methyl groups attached to the amide nitrogen is replaced by hydrogen while the other is replaced by a 3-carboxyphenyl group. The sodium salt is used for the treatment of moderate to severe susceptible infections including intra-abdominal and acute gynaecological infections, pneumonia, and infections of the skin and of the urinary tract. It has a role as an antibacterial drug. It is a carbapenemcarboxylic acid and a pyrrolidinecarboxamide. It is a conjugate acid of an ertapenem(1-).