Poisoning wood alcohol (methanol)

General or Other | Emergency Medicine | Poisoning wood alcohol (methanol) (Disease)


Description

Methanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH (often abbreviated MeOH). It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol (drinking alcohol).

Symptoms of methanol poisoning usually do not appear until 12 to 24 h after ingestion, when sufficient toxic metabolites have accumulated. Manifestations include headache, dizziness, nausea, vomiting, vasomotor disturbances, central nervous system depression, and respiratory failure.

Causes and Risk factors

Methanol is extremely poisonous. As little as 2 tablespoons can be deadly to a child. About 2 to 8 ounces can be deadly for an adult.

Visual disturbance is almost universal and ranges from mild blurring of vision to total blindness. Impairment of vision may be transient, but permanent blindness may follow survival of the acute intoxication. The pupils are dilated and nonreactive, and there is hyperemia of the optic disc and retinal edema. Acidosis is commonly severe.

Diagnosis and Treatment

In the treatment of methyl alcohol intoxication emesis and gastric lavage are of use only within the first 2 h after ingestion. Intravenous administration of large amounts of sodium bicarbonate combats acidosis.

Return of acidosis is frequent after initial correction, and additional alkali must be administered as indicated by close observation of the patient and laboratory determinations. It is most useful to obtain a blood methanol level as soon as possible. ...