Comparative Pharmacology
Head-to-head clinical analysis: ANTIZOL versus FOMEPIZOLE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ANTIZOL versus FOMEPIZOLE.
ANTIZOL vs FOMEPIZOLE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Antizol (fomepizole) is a competitive inhibitor of alcohol dehydrogenase, the enzyme that catalyzes the oxidation of ethanol to acetaldehyde. It also inhibits the metabolism of ethylene glycol and methanol to their toxic metabolites.
Fomepizole is a competitive inhibitor of alcohol dehydrogenase, the enzyme that catalyzes the first step in the metabolism of ethylene glycol and methanol to their toxic metabolites. By inhibiting alcohol dehydrogenase, fomepizole prevents the formation of toxic metabolites such as glycolic acid, glyoxylic acid, and oxalic acid from ethylene glycol, and formic acid from methanol.
Initial: 15 mg/kg IV over 10 minutes, then 3 mg/kg IV every 4 hours for 2 doses, then 3 mg/kg IV every 6 hours for 4 doses.
Loading dose of 15 mg/kg intravenously over 15 minutes, followed by 10 mg/kg every 12 hours for 4 doses, then 15 mg/kg every 12 hours if ethanol co-ingestion is present; otherwise 10 mg/kg every 12 hours until ethylene glycol or methanol levels <20 mg/dL.
None Documented
None Documented
Clinical Note
moderateFomepizole + Artesunate
"The serum concentration of the active metabolites of Artesunate can be reduced when Artesunate is used in combination with Fomepizole resulting in a loss in efficacy."
Terminal elimination half-life: 2.5-3.5 hours in adults. Clinical context: Dose adjustment recommended in severe renal impairment (CrCl <30 mL/min) due to prolonged half-life.
Terminal: 5-7 hours in healthy adults; prolonged to 8-14 hours in patients with ethanol co-ingestion due to competitive inhibition; no significant change in severe renal impairment.
Renal: 80-95% as parent drug and metabolites. Fecal: <5%. Biliary excretion is negligible.
Renal: 70-90% as unchanged drug and metabolites (4-carboxypyrazole, 4-hydroxymethylpyrazole); biliary/fecal: minor (<5% total).
Category C
Category C
Antidote
Antidote