Fatal dose of methanol is?
Ans. is 'b' i.e., 150 ml * Methanol is highly toxic alcohol. It is metabolized to formaldehyde (by alcohol dehydrogenase) and formic acid (by acetaldehyde dehydrogenase). It can be present in contaminated country liquor used to denature ethanol.* It is the accumulation of formic acid which causes toxic effects in methanol poisoning. Accumulation of formic acid results in lactic acidosis/high anion gap metabolic acidosis with low plasma bicarbonates, blindness due to retinal damage, papilledema and optic atrophy.* Symptoms of poisoning are nausea, vomiting, dizziness, confusion, headache, abdominal pain, respiratory depression, cyanosis, acute tubular necrosis, hypothermia, fixed dilated pupils, visual distrubance (blurring of vision; photophobia) and odor of spirit in breath. Fatal dose in adults is 60-240 ml in adults, but as little as 15 ml can cause blindness.* Methanol poisoning can be treated by supportive measures, gastric lavage and sodium bicarbonate (to treat acidosis) ethanol is useful because it competitively inhibits the conversion of methanol to formic acid. Fomepizole can also be used as it is a specific inhibitor of alcohol dehydrogenase. Folic acid or folinic acid enhance the metabolism of formic acid to C02. Hemodialysis may also be used in severe poisoning.
15 ml
150 ml
500 ml
650 ml
Toxicology