4226. Fomepizole

Nomenclature

CAS number: 7554-65-6
4-Methyl-1H-pyrazole; 4-MP; Antizol (Orphan Med.).
C4H6N2; mol wt 82.10.
C 58.52%, H 7.37%, N 34.12%.

Description and references

Alcohol dehydrogenase inhibitor. Prepn: H. Pechmann, E. Burkard, Ber. 33, 3590 (1900); D. S. Noyce et al., J. Org. Chem. 20, 1681 (1955); T. Momose et al., Heterocycles 30, 789 (1990). Inhibition of human liver alcohol dehydrogenase: T.-K. Li, H. Theorell, Acta Chem. Scand. 23, 892 (1969). Toxicity study: G. Magnusson et al., Experientia 28, 1198 (1972). GC determn in plasma and urine: R. Achari, M. Mayersohn, J. Pharm. Sci. 73, 690 (1984). Clinical pharmacology: D. Jacobsen et al., Alcohol. Clin. Exp. Res. 12, 516 (1988). Pharmacokinetics: eidem, Eur. J. Clin. Pharmacol. 37, 599 (1989). Clinical trial in ethylene glycol poisoning: J. Brent et al., N. Engl. J. Med. 340, 832 (1999); in methanol poisoning: idem et al., ibid. 344, 424 (2001). Review: J. Likforman et al., J. Toxicol. Clin. Exp. 7, 373-382 (1987). Review of use in methanol poisoning: M. B. Mycyk, J. B. Leikin, Am. J. Ther. 10, 68-70 (2003).

Chemical structure

Properties

mp 15.5-18.5°. bp18mm 98.5-99.5°; bp730 204-205°. nD22 1.4913. uv max in 95% ethanol: 220 nm (log ε 3.47); in 6N HCl: 226 nm (log ε 3.65). Sol in water, alcohol. LD50 (7 days) in mice, rats (mmol/kg): 3.8, 3.8 i.v.; 7.8, 6.5 orally (Magnusson).

Therapeutic Category

Antidote to methanol and ethylene glycol poisoning.

Therapeutic Category (Veterinary)

Antidote to ethylene glycol poisoning in dogs.

Keywords

Antidote (Methanol and Ethylene Glycol Poisoning)