Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:
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- Colorless, volatile liquid
- Absorbed in 30–60 min
- Metabolized by liver
- Half-life 4–8 hr
- Metabolites of formaldehyde and formic acid produce toxic effects.
- Inhibits cytochrome oxidase.
- Formic acid:
- Determines degree of acidosis, visual symptoms, and mortality
- Directly toxic to retinal and optic nerve tissue
- Methanol metabolism:
- Step 1: Methanol is converted to formaldehyde by liver enzyme alcohol dehydrogenase.
- Step 2: Formaldehyde is then rapidly converted by aldehyde dehydrogenase to formic acid.
- Step 3: Formic acid is degraded to carbon dioxide and water by folate-dependent mechanism.
- Steps 1 and 3 are rate-limiting steps.
EtiologyCommon sources of methanol:
- Wood alcohol
- Windshield washer fluid (> 60% cases)
- Inhalational abuse of carburetor cleaners
- Fuel antifreeze solutions
- Paint solvents
- Household cleaners
- Sterno cans
- Model airplane fuel
- Photocopying fluid