The antidotes for ethylene glycol poisoning are ethanol and fomepizole. This antidotal treatment forms the mainstay of management of ethylene glycol poisoning. The toxicity of ethylene glycol comes from its metabolism to glycolic acid and oxalic acid. The goal of pharmacotherapy is to prevent the formation of these metabolites. Ethanol acts by competing with ethylene glycol for alcohol dehydrogenase (ADH), the first enzyme in the degradation pathway. Because ethanol has nearly 100 times more affinity for ADH, it blocks the breakdown of ethylene glycol into glycolaldehyde, thus preventing further degradation to oxalic acid and the associated nephrotoxic effects. The unreacted ethylene glycol remains in the body and is eventually excreted in the urine; however, supportive therapy for the CNS depression and metabolic acidosis will be required until the ethylene glycol concentrations fall below toxic limits. Pharmaceutical grade ethanol is usually given intravenously as a 5 or 10% solution in 5% dextrose, but it is also sometimes given orally in the form of a strong spirit such as whisky, vodka, or gin.Fomepizole is a potent inhibitor of alcohol dehydrogenase; similar to ethanol, it acts to block the formation of the toxic metabolites. Fomepizole has been shown to be highly effective as an antidote for ethylene glycol poisoning. It is the only antidote approved by the U.S. Food and Drug Administration for the treatment of ethylene glycol poisoning. Both antidotes have advantages and disadvantages. Ethanol is readily available in most hospitals, is inexpensive, and can be administered orally as well as intravenously.
Three follow up studies targeting limited populations or suicidal persons to assess the efficacy of bittering agents in preventing toxicity or death have, however, shown limited benefit of bittering ethylene glycol preparations in these two populations. Specifically, Mullins finds that bittering of antifreeze does not reduce reported cases of poisoning of preschoolers in the US state of Oregon. Similarly, White found that adding bittering agents did not decrease the frequency or severity of antifreeze poisonings in children under the age of 5. Additionally, another study by White found that suicidal persons are not deterred by the bittered taste of antifreeze in their attempts to kill themselves. These studies did not focus on poisoning of domestic pets or livestock, for example, or inadvertent exposure to bittered antifreeze among a large population (of non-preschool age children). Poisoning of a raccoon was diagnosed in 2002 in Prince Edward Island, Canada. An online veterinary manual provides information on lethal doses of ethylene glycol for chicken, cattle, as well as cats and dogs, adding that younger animals may be more susceptible. History
Ethylene glycol was once thought innocuous; in 1931 it was suggested as being suitable for use as a vehicle or solvent for injectable pharmaceutical preparations. Numerous cases of poisoning have been reported since then, and it has been shown to be toxic to humans. Environmental effects
Ethylene glycol involved in aircraft de-icing and anti-icing operations is released onto land and eventually to waterways.