Amylase - blood

Definition

Amylase is an enzyme that helps digest carbohydrates. It is made in the pancreas and the glands that make saliva. When the pancreas is diseased or inflamed, amylase releases into the blood.

A test can be done to measure the level of this enzyme in your blood.

Amylase may also be measured with an amylase urine test.

Alternative Names

Pancreatitis - blood amylase

How the Test is Performed

A blood sample is taken from a vein.

How to Prepare for the Test

No special preparation is needed. However, you should avoid alcohol before the test. The health care provider may ask you to stop taking drugs that may affect the test. DO NOT stop taking any medicines without first talking to your provider.

Drugs that can increase amylase measurements include:

• Asparaginase
• Aspirin
• Birth control pills
• Cholinergic medicines
• Ethacrynic acid
• Methyldopa
• Opiates (codeine, meperidine, and morphine)
• Thiazide diuretics

How the Test will Feel

You may feel slight pain or a sting when the needle is inserted to draw blood. Afterward, there may be some throbbing.

Why the Test is Performed

This test is most often used to diagnose or monitor acute pancreatitis. It may also detect some digestive tract problems.

The test may also be done for the following conditions:

• Chronic pancreatitis
• Pancreatic pseudocyst

Normal Results

The normal range is 40 to 140 units per liter (U/L) or 0.38 to 1.42 microkat/L (µkat/L).

Normal value ranges may vary slightly among different laboratories. Some laboratories use different measurement methods. Talk to your provider about the meaning of your test results.

What Abnormal Results Mean

Increased blood amylase level may occur due to:

• Acute pancreatitis
• Cancer of the pancreas, ovaries, or lungs
• Cholecystitis
• Gallbladder attack caused by disease
• Gastroenteritis (severe)
• Infection of the salivary glands (such as mumps) or a blockage
• Intestinal blockage
• Macroamylasemia
• Pancreatic or bile duct blockage
• Perforated ulcer
• Tubal pregnancy (may have burst open)

Decreased amylase level may occur due to:

• Cancer of the pancreas
• Damage to the pancreas with pancreatic scarring
• Kidney disease
• Toxemia of pregnancy

Risks

Slight risks from having blood drawn may include:

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

References

Crockett SD, Wani S, Gardner TB, Falck-Ytter Y, Barkun AN; American Gastroenterological Association Institute Clinical Guidelines Committee. American Gastroenterological Association Institute guideline on initial management of acute pancreatitis. Gastroenterology. 2018;154(4):1096-1101. PMID: 29409760 www.ncbi.nlm.nih.gov/pubmed/29409760.

Forsmark CE. Pancreatitis. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 144.

Meisenberg G, Simmons WH. Digestive enzymes. In: Meisesnberg G, Simmons WH, eds. Principles of Medical Biochemistry. 4th ed. Philadelphia, PA: Elsevier; 2017:chap 20.

Tenner S, Steinberg WM. Acute pancreatitis. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology/Diagnosis/Management. 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 58.