15. Methanol intoxication

Question 1

Where can Methanol be found?

Answer 1

1. Naturally in anaerobic metabolism of bacteria.
2. Industrially by catabolic processes from carbon monoxide, dioxide and hydrogen.

Question 2

What are the treatment options for Methanol Intoxication?

Answer 2

1. Gastric lavage
2. Activated charcoal
3. Sympathomatic treatment
4. Alkali therapy
5. Ethanol (blood ethanol level must be approx. 0.1%)

Question 3

What are the signs and symptoms of chronic methanol intoxication?

Answer 3

1. Visual problems
2. CNS problems (extrapyramidal)
3. Acustic neuritis
4. Peripheral polyneuritis

Question 4

What are the symptoms of methanol intoxication?

Answer 4

1. Drunkeness (weak narcotic effect of methanol).
2. Theu: 8-36 h latency period after that abdominal pain, dyspnea, visual distrubances, blindness, delirium, seizures, coma and eventually death.
3. Formaldehyde and formic acid cause acidosis and they have specific toxic effects on retinal cells.

Question 5

How is the metabolism of Methanol in the body?

Answer 5

Methanol is converted to formaldehyde and then to formic acid. The enzyme involved is Alcohol Dehydrogenase. Methanol and Ethanol competitively bind to this enzyme and does therefore have some therpeutic value. Formaldehyde and Formic acid are responsible for the intoxication of Methanol.

Question 6

What are the routes of exposure to methanol?

Answer 6

Because it taste and smell similar to ethanol it is usually via oral intoxication. It has good absorption and wide distribution.