Methanol Ingestion: What Happens in Your Body in the First 4 Hours

Methanol is a highly toxic type of alcohol used in solvents, fuels, cleaners, and, unfortunately, found in some adulterated beverages. Even small amounts can cause severe and irreversible damage.

But what really happens in the body after methanol ingestion?

In the initial moments, symptoms resemble common drunkenness: dizziness, nausea, headache, and abdominal pain. This is the most deceptive phase. The liver begins to convert methanol into formaldehyde and, subsequently, into formic acid—a substance that interferes with cellular respiration and intoxicates the body.

During this period, the patient may appear stable, but the body is already entering metabolic collapse.

With the accumulation of formic acid, the blood becomes more acidic, leading to what is known as metabolic acidosis. The eyes are particularly sensitive to this process: blurred vision, photophobia, and the sensation of a “rain of pixels” emerge, as if small luminous points float in the visual field. These signs indicate damage to the optic nerve, which can become irreversible if treatment is not initiated promptly.

As acidosis progresses, the body begins to collapse. The nervous system is the first to feel it: mental confusion, seizures, and decreased consciousness can evolve into a coma. Without immediate medical intervention—such as hemodialysis and the use of specific antidotes (ethanol or fomepizole)—the risk of organ failure and death is very high.

Suspicion should be immediate in cases of intoxication from beverages of questionable origin. Hospital treatment includes and should be guided by physicians only:

Use of ethanol or fomepizole, which prevent the metabolism of methanol into formic acid;

Hemodialysis, to rapidly eliminate toxins from the blood.

Seek immediate medical attention if suspicious symptoms appear after consuming any alcoholic beverage.

Methanol is a substance with high toxicity potential. The interval between the first symptoms and systemic collapse can be short—and early treatment is the only chance to avoid severe sequelae, such as blindness or death.

At Clínica Revitalize, we value information as a form of prevention. Taking care of your health also means recognizing risks that often go unnoticed.

This content is part of Clínica Revitalize's commitment to translating science into accessible clinical practice — without losing rigor or depth.