Swissmedic announces new contraindication for all medicinal products containing metronidazole or another nitroimidazole.
Summary
- At present the medicinal product information for medicinal products containing metronidazole that are authorised for systemic use in Switzerland includes a warning that metronidazole should only be used after a careful assessment of the risks and benefits owing to cases of severe hepatotoxicity/acute liver failure in patients with Cockayne syndrome [note: a very rare, autosomal recessive disorder].
- Swissmedic has carried out another risk assessment, which found that in the light of the published case reports and other literature, it should be assumed that metronidazole treatment will cause acute liver failure in the vast majority of, if not all, patients with Cockayne syndrome. The pathological mechanism is unknown.
- The cases described occurred after systemic use of metronidazole. The consensus in the literature is that patients with Cockayne syndrome must not be treated with metronidazole and that other nitroimidazoles should not be used because of their structural similarity to metronidazole.
- Swissmedic has also concluded that nitroimidazoles must not be used in patients with Cockayne syndrome. The new contraindication applies to all pharmaceutical forms, i.e. including vaginal and topical nitroimidazoles.
For further information, please refer to the information letter.