United States of America. The Food and Drug Administration has approved fomepizole (Antizol: Orphan Medical) as an antidote for ethylene glycol poisoning and in cases of suspected ethylene glycol ingestion.

Ethylene glycol is a sweet-tasting compound that has wide commercial use as a preservative, antifreeze, coolant and glycerol substitute. It is commonly used in attempted suicides and ingestion can be fatal. Ethylene glycol has intoxicating properties similar to those of alcohol, and its metabolites cause central nervous system, renal and cardiopulmonary dysfunction together with severe metabolic acidosis.

The use of fomepizole is recommended if ethylene glycol serum levels are above 20 mg/dl or if ingestion of ethylene glycol is suspected. In cases where ethylene glycol levels are equal to or above 50 mg/dl, or when the patient has renal failure or worsening metabolic acidosis, haemodialysis should also be considered. Haemodialysis removes fomepizole, therefore doses must be given more frequently during haemodialysis.

References: FDA Orphan Products approved for Marketing, December 1997 & April 1998, in: INFORx-MED Vol. 16, No. 7, July 1998, Medicines Information Centre, Cape Town, South Africa.