Staphylococcal endocarditis treated by intravenous administration of fusidic acid and penicillin

Fusidic acid in septicaemia and endocarditis

The in vitro activity of fusidic acid against Staphylococcus aureus is confirmed in clinical studies which demonstrate that this antibiotic in combination with other agents, particularly beta-lactams, is efficacious in non-MRSA septicaemia. Some reports suggest that fusidic acid when used in combination, may significantly diminish the risk of relapse after cessation of therapy. However, in spite of over 30 years of use and its recommendation in a number of guidelines, published evidence is insufficient to allow reliable comment on the efficacy of the antibiotic in the treatment of endocarditis.

Fusidic acid adverse drug reactions

Unlike trials conducted today on new antimicrobials, the introduction of fusidic acid was not accompanied by extensive studies on toxicity and side effects. The early studies on small numbers of patients reported fusidic acid to be a nontoxic drug with the main side effects being gastrointestinal tract discomfort, diarrhoea and headache. Case reports of hepatotoxicity were reported from 1972. A retrospective analysis showed this to be reversible and mainly associated with intravenous administration. Rarely reported side effects are granulocytopenia, thrombocytopenia and venous spasm. Skin reactions, including contact dermatitis, are uncommon. After many years of use the most common side effects reported for fusidic acid are minor and relate to the gastrointestinal tract.