American Board of Internal Medicine (ABIM) Certification Practice Exam

In the context of treating ethylene glycol intoxication, which other treatment option is typically considered along with sodium bicarbonate?

1. Activated charcoal

2. Fomepizole

3. Insulin therapy

4. Vitamin C

The correct answer is: Fomepizole

In the case of ethylene glycol intoxication, fomepizole is a key treatment option used alongside sodium bicarbonate. Ethylene glycol is metabolized in the liver to toxic metabolites, including glycolic acid and oxalic acid, which can lead to severe metabolic acidosis and renal failure. The purpose of administering fomepizole is to inhibit the enzyme alcohol dehydrogenase, which is responsible for the conversion of ethylene glycol into its toxic metabolites. By blocking this enzyme, fomepizole effectively prevents further production of these harmful substances, providing a critical window for supportive care and the correction of metabolic derangements. Sodium bicarbonate is used to address the acidosis that results from the accumulation of these metabolites. Together, sodium bicarbonate and fomepizole effectively reduce the burden of metabolic acidosis and limit the toxicity caused by ethylene glycol. Other treatments listed, while they have their uses in different contexts, do not serve the same complementary purpose in the acute management of ethylene glycol intoxication.