Meropenem

Some of the views expressed in the following notes on newly approved products should be regarded as preliminary, as there may have been limited published data at the time of publication, and little experience in Australia of their safety or efficacy. However, the Editorial Executive Committee believes that comments made in good faith at an early stage may still be of value. Before new drugs are prescribed, the Committee believes it is important that more detailed information is obtained from the manufacturer's approved product information, a drug information centre or some other appropriate source.

Merrem IV (ICI Australia Operations)
vials containing 250 mg, 500 mg and 1 g

Indication: specified infections
The carbapenems are antibiotics with a beta lactam structure. Imipenem was the first drug of the class, but as it was inactivated by renal dipeptidase, it had to be formulated with cilastatin, a dipeptidase inhibitor. Meropenemis a carbapenem which is not affected by renal dipeptidase.

Organisms which are sensitive to meropenem include streptococci and staphylococci, Escherichia coli, Haemophilus influenzae, Moraxella catarrhalis, Klebsiella pneumoniae and Bacteroides fragilis. Some strains of Pseudomonasaeruginosa are susceptible to meropenem. In view of its bactericidal activity against many aerobic and anaerobic bacteria, the drug has been approved for several indications. It can be used to treat severe infections of the lower respiratory tract, urinary tract, skin and skin structures, meningitis, septicaemia,febrile neutropenia, intra-abdominal and gynaecological infections.

Meropenem is given intravenously by infusion or slow injection every 8 hours. Most of the dose is excreted unchanged in the urine within 12hours. The half-life is approximately one hour.

Patients who are hypersensitive to penicillins may also be hypersensitive to meropenem. The drug is generally well tolerated, but children may be more prone to adverse effects. The adverse reactions include rashes, headache, thrombocytopenia, altered liver function, nausea and vomiting.

Most hospitals control the prescription of carbapenems. Meropenem should be restricted to serious infections where other antibiotics are contra indicated or ineffective.