Methanol test

Definition

Methanol is a nondrinking type of alcohol used for industrial and automotive purposes. A test can be done to measure the amount of methanol in your blood.

See also: Methanol poisoning

Why the Test is Performed

This test is done to see if you have methanol in your body. Some people accidentally drink methanol, or intentionally drink it as a substitute for grain alcohol (ethanol).

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. Methanol poisoning mainly affects the gastrointestinal, nervous, and ophthalmological (eye) systems.

How the Test is Performed

Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.

Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm.

Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.

The blood is then analyzed in a laboratory.

How to Prepare for the Test

No special preparation is necessary.

How the Test Will Feel

When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

Risks

Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight but may include:

• Excessive bleeding
• Fainting or feeling light-headed
• Hematoma (blood accumulating under the skin)
• Infection (a slight risk any time the skin is broken)

Normal Results

No presence of methanol is normal.

What Abnormal Results Mean

No amount of methanol is normally found in the body. Its presence indicates possible poisoning.