Disulfiram-ETOH interaction - Part 2

 Case: 44 years old male who is on Disulfiram maintenance treatment with alcohol (ETOH) abstinence is admitted to ICU with chest pain, sweating, headache, dyspnea, flushing, palpitations, nausea, and vomiting. Cardiac etiology has been ruled out. Patients report some viral flu-like symptoms lately and use over-the-counter cough medicine. Patient failed supportive treatment with anti-emetics, IV resuscitations, and diphenhydramine. Which antidote can be considered?

Answer: Fomepizole

Disulfiram has been used as a medical treatment for ETOH abuse. After 2 days of abstinence, disulfiram can be started with a dose of 250 to 500 mg/day for one to two weeks, followed by a maintenance dose if needed.

Disulfiram discourages ETOH drinking by causing an accumulation of acetaldehyde, alcohol’s primary metabolite - resulting in symptoms as described above in our case.

If the patient accidentally consumes ETOH, which is frequently present in many over-the-counter symptom-relieving drugs or mouthwashes, the patient may experience the said symptoms. The treatment is supportive. Hypotension is common and may require IV resuscitations, pressor, and Trendelenburg positioning. Diphenhydramine may be of good help. 

These patients may have some EKG changes despite clean coronaries but need to be ruled for any cardiac injury. 

If the patient does not respond to supportive treatment, Fomepizole should be considered. Fomepizole, a 4-methylpyrazole, helps patients with severe presentations. It is suggested because it blocks alcohol dehydrogenase and is expected to reverse disulfiram reactions.

Caution should be exercised in pregnant patients, as limb-reduction anomalies in infants born to disulfiram-treated alcoholic mothers have been reported.

#toxicology

References:

1. Schicchi A, Besson H, Rasamison R, et al. Fomepizole to treat disulfiram-ethanol reaction: a case series. Clin Toxicol (Phila) 2020; 58:922.

2. Sande M, Thompson D, Monte AA. Fomepizole for severe disulfiram-ethanol reactions. Am J Emerg Med 2012; 30:262.e3.

3. Reitnauer PJ, Callanan NP, Farber RA, Aylsworth AS. Prenatal exposure to disulfiram implicated in the cause of malformations in discordant monozygotic twins. Teratology 1997; 56:358.

4. Nora AH, Nora JJ, Blu J. Limb-reduction anomalies in infants born to disulfiram-treated alcoholic mothers. Lancet 1977; 2:664.

5. Center for Substance Abuse Treatment. Incorporating Alcohol Pharmacotherapies Into Medical Practice, Substance Abuse and Mental Health Services Administration (US), Rockville, MD 2009.