A glucagon test measures the amount of a hormone called glucagon in your blood. Glucagon is produced by cells in the pancreas. It helps control blood sugar levels.

Blood is typically 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.

A specific laboratory technique called radioimmunoassay (RIA) is used to check for the hormone glucagon in the blood.

Your health care provider will tell you if you need to fast for a period of time before the test.

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.

Glucagon stimulates the liver to release glucose. As the level of blood sugar decreases, the pancreas releases more glucagon, and vice versa.

Your health care provider may measure your glucagon levels if you show symptoms of:

• Low blood sugar (hypoglycemia)
• Mild diabetes
• A skin rash called necrolytic migratory erythema
• Unexplained weight loss

The normal range is 50 - 100 pg/mL.

Note: pg/mL = picograms per milliliter

Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

• Abnormal glucagon levels may be due to multiple endocrine neoplasia (MEN) type I.
• In a rare syndrome, a tumor in the pancreas called a glucagonoma can produce excess glucagon and cause diabetes.
• People with insulin resistance or type 2 diabetes often produce very high levels of glucagon.

Veins 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)