About the Test
Purpose of the test
The blood amylase test is used to help diagnose and monitor acute pancreatitis. This test may also diagnose and monitor chronic pancreatitis and other disorders involving the pancreas.
The blood amylase test may be used along with a lipase test to detect pancreatic diseases. While the amylase test is sensitive for pancreatic diseases, it is not specific. That means an elevated amylase level may indicate a problem, but the cause may not necessarily be related to the pancreas. Besides the pancreas, amylase can also come from other inflamed or damaged tissues and organs such as salivary glands, intestines, and ovaries.
The lipase test, on the other hand, is more specific than amylase for diseases of the pancreas, particularly for acute pancreatitis and acute alcoholic pancreatitis. An elevated lipase usually indicates a problem with the pancreas. Evaluating the results of the two tests together helps diagnose or rule out pancreatitis and other conditions.
A urine amylase test may also be used to detect pancreatic diseases. Typically, its level will mirror blood amylase concentrations, but the rise and fall will occur later. Sometimes a urine creatinine level may be ordered along with the urine amylase. The ratio of amylase to creatinine can be calculated and used to assess kidney function.
In certain cases, for example, when fluid is accumulated in the abdomen (ascites), an amylase test may be performed on peritoneal fluid to help diagnose pancreatitis.
Amylase tests are sometimes used to monitor the treatment of pancreatic cancer and after the removal of gallstones that have caused gallbladder attacks.
What does the test measure?
Amylase is an enzyme produced primarily by the pancreas and the salivary glands to help digest carbohydrates. This test measures the amount of amylase in the blood or urine or sometimes in peritoneal fluid, the fluid found between the membranes that cover the abdominal cavity and the outside of the abdominal organs.
The pancreas is a narrow, flat organ about 6 inches long located deep within the abdominal cavity, below the liver and between the stomach and the spine. Inside the pancreas, small ducts (tubes) feed digestive enzymes produced by the pancreas into the pancreatic duct. The pancreas releases amylase through the pancreatic duct into the first part of the small intestine, where it helps break down dietary carbohydrates.
Amylase is usually present in the blood and urine in small quantities. When cells in the pancreas are injured, increased amounts of amylase are released into the blood. This also increases amylase concentrations in the urine because amylase is eliminated from the blood through the urine.
Increased amylase levels can occur with pancreatitis, which is inflammation of the pancreas, or when the pancreatic duct is blocked by a gallstone or, in rare cases, with a pancreatic tumor.
When should I get this test?
A blood amylase test may be ordered if you have signs or symptoms of a pancreatic disorder, such as:
- Severe upper abdominal pain that radiates to the back or feels worse after eating
- Loss of appetite
- Nausea, vomiting
- Yellowing of the eyes or skin (jaundice)
- Rapid pulse
- Loose, fatty, foul-smelling stools (steatorrhea)
A urine amylase test may be ordered along with or following a blood amylase test. One or both may also be ordered periodically if your health care practitioner wants to monitor or evaluate the effectiveness of treatment and determine whether amylase levels increase or decrease over time.
Finding an Amylase Test
How can I get an amylase test?
Typically, an amylase test will be done in your doctor’s office or another medical setting like a laboratory or hospital. These tests are normally ordered by a doctor but may be available without a doctor’s orders.
Can I take the test at home?
Amylase tests are not available at home.
How much does the test cost?
The cost of an amylase test varies depending on where it is performed and whether or not you have health insurance, which typically covers the cost if your doctor orders it to diagnose or treat a medical condition. You can always ask your physician, the lab, or your insurance provider about any out-of-pocket costs you may have.
Taking an Amylase Test
An amylase test is done with a blood sample obtained by inserting a needle into a vein in the arm. Sometimes a random urine sample, a 24-hour urine sample, or peritoneal fluid is collected.
Before the test
For both a blood test and a urine sample, avoid alcohol for 24 hours before the test. With the blood test, you may be instructed not to eat or drink anything other than water for two hours before blood is drawn. Certain medications can affect amylase levels, so discuss medications with your doctor before testing is done.
During the test
To collect the blood specimen for an amylase test, a phlebotomist draws from a vein in your arm. After locating the vein, they will tie an elastic band around your upper arm to increase the blood flow and may ask you to make a fist. They then clean the area with an alcohol swab and insert the needle into the vein. The blood will be collected into a tube.
You may feel a pinch or mild discomfort during the blood draw, but it should subside when the needle is removed.
If you are having your urine tested, you will be given a urine collection cup to urinate directly into; you will close it and give the specimen to the lab or doctor.
After the test
After completing a blood test, the health care provider will apply a bandage and may tell you to apply some pressure on the site for a few minutes. You can usually remove the bandage after a couple of hours, and shouldn’t have any restrictions. There may be minor bruising at the draw site.
Amylase Test Results
Receiving test results
Results are normally available within two business days of taking an amylase test. Your doctor or laboratory may call, email, or text you with the results. You can sometimes log in to a patient portal to view results if available.
Interpreting test results
A high amylase level in the blood may indicate the presence of a condition affecting the pancreas. In acute pancreatitis, amylase in the blood often increases to four to six times higher than the highest reference value, sometimes called the upper limit of normal. The increase occurs within four to eight hours of injury to the pancreas and generally remains elevated until the cause is successfully treated.
The amylase values will then return to normal in a few days.
Amylase and lipase results may be interpreted together. In acute pancreatitis, lipase levels usually rise at about the same time as blood amylase levels, about three to six hours after injury. Still, lipase levels will remain elevated longer than amylase levels. Lipase testing is considered more reliable than amylase testing for the initial diagnosis of acute pancreatitis.
In chronic pancreatitis, amylase levels initially will be moderately elevated but often decrease over time with progressive pancreas damage. In this case, levels returning to normal may not mean that the source of damage has been resolved. The magnitude of the increase in amylase level does not indicate the severity of pancreatic disease.
Amylase levels may also significantly increase if you have pancreatic duct obstruction and pancreatic cancers.
In general, urine amylase levels rise in proportion to blood amylase levels and stay elevated for several days after blood levels return to normal.
An increased amylase level in peritoneal fluid can occur in acute pancreatitis but may also occur in other abdominal disorders, such as obstructed intestine or decreased blood flow to the intestines (infarct).
If you have pancreatitis symptoms, a low amylase level in blood and urine may indicate permanent damage to the amylase-producing cells in the pancreas. Decreased levels can also be due to kidney disease and pre-eclampsia.
Increased blood amylase levels with normal to low urine amylase levels may indicate a macroamylase, a benign complex of amylase and other proteins that accumulates in the blood.
Amylase levels may also be significantly increased in people with gallbladder attacks. Urine and blood amylase levels may be moderately elevated with a variety of other conditions, such as ovarian cancer, lung cancer, tubal pregnancy, acute appendicitis, diabetic ketoacidosis, mumps, intestinal obstruction and infarction, or perforated ulcer, but amylase tests are not generally used to diagnose or monitor these disorders.
Ask your doctor about your amylase test results once they are available. Some questions can include:
- What does my amylase level mean?
- What might be causing an abnormal amylase level?
- What follow-up testing is needed to confirm a diagnosis?