Substance
Methanol

Pathology
Metabolism to formaldehyde and formic acid.

Symptoms
Latent period (24–72 hr) before development of symptoms, dizziness, inebriation, blurred vision, headache, nausea, vomiting, abdominal pain, delirium, visual disturbances that may progress to blindness, weak and rapid pulse, shallow respirations, cyanosis, coma, metabolic acidosis, respiratory failure, death.

Emergency Measures
Activated charcoal for recent ingestion, ethanol IV or orally to inhibit toxic metabolites, hemodialysis in severe cases, aggressive management of metabolic acidosis. Folic acid and 4-methylpyrazole can be used as antidotes.

Comments
Visual impairment, optic atrophy, and blindness are due to effects of formic acid on the optic nerve.