Amylase: what it is, what it tells you and when it’s tested

Amylase is an enzyme that helps you digest starch, like bread and pasta. It is made mostly by the pancreas and the salivary glands. A small amount always reaches your blood. If one of these organs is inflamed, or your kidneys clear it less well, the level in your blood rises.

When it’s tested

Doctors mostly order it when there is strong pain in the upper belly and they suspect acute pancreatitis. In the emergency department it is one of the most common tests for this pain.

It is also used to follow a known pancreas condition, or when the salivary glands are swollen.

It is not a useful test for people who feel well. With no symptoms, a slightly high amylase often just leads to more tests, and often nothing is found. That is why Rosa does not test it. Instead it measures triglycerides, bilirubin and gamma GT, linked to the most common causes of pancreatitis, and creatinine for your kidneys.

What it tells you, and what it does not

Together with strong belly pain, an amylase more than three times above the limit points to acute pancreatitis. It rises in the first hours and returns to normal within a few days.

On its own it is not enough. It does not say how severe the pancreatitis is or what caused it. And it can rise for reasons that have nothing to do with the pancreas.

Today many doctors prefer lipase: it is more precise for the pancreas and stays high for longer.

That is why it is read together with other tests:

• Lipase: The more precise enzyme for the pancreas
• Triglycerides: Very high levels can cause pancreatitis
• Bilirubin: It rises if a gallstone blocks the bile ducts
• Creatinine: If your kidneys work less well, amylase rises

Normal amylase levels

The lab decides what is normal. For total amylase, many lab reports give 28 to 100 U/L. Others use slightly different limits, for example up to 110 or 125 U/L: the one on your report is what counts.

Some labs measure only pancreatic amylase, the part that comes from the pancreas. Its limits are lower. Check which of the two is on your report.

What your result means

Find the row for your result, in U/L. The table is for total amylase. If your report says pancreatic amylase, use the limits printed there.

• Below 28: Low. Usually it means nothing. Rarely it is seen when the pancreas has worked poorly for many years. Usually nothing to do. If you have greasy diarrhoea or lose weight for no reason, talk to your doctor.
• 28 to 100: Normal. Your value sits in the range many labs call normal. Nothing to do.
• Above 100, up to 300: High. A mild rise is common. It often comes from the salivary glands, the kidneys or macroamylase, a harmless amylase bound to blood proteins. With no pain, talk to your doctor: they usually repeat the test and check lipase.
• Above 300: Very high. With a limit of 100, this is more than three times the limit. With strong belly pain, it points to acute pancreatitis. With strong belly pain, call 112 or go to the emergency department. With no pain, see your doctor soon.

If your amylase is high or low

• High amylase: With strong pain it can be pancreatitis. With no pain, it often comes from saliva, the kidneys or harmless causes.
• Low amylase: Usually it means nothing. Rarely it is seen when the pancreas has worked poorly for years.

What can skew the result

A few things raise it without the pancreas being ill.

• Kidneys that filter less: Amylase leaves your body in urine. If your kidneys work less well, it stays in your blood for longer.
• Salivary glands: Mumps or a stone in a salivary gland raises it.
• Macroamylase: Sometimes amylase binds to blood proteins and cannot pass into urine. The value stays high, but it is harmless.
• Alcohol: Heavy drinking can raise it, even without pancreatitis.

When to worry

Watch for these cases:

• You have strong, constant pain in the upper belly that spreads to your back, often with nausea or vomiting: call 112 or go to the emergency department.
• Your amylase is above the limit on your report, even with no pain: talk to your doctor.
• It is more than three times the limit: see your doctor soon.
• It stays high for months with no clear reason: your doctor usually checks lipase and your kidneys, and sometimes asks for an ultrasound scan.

Frequently asked questions

What are normal amylase levels? For total amylase, many lab reports give 28 to 100 U/L. Pancreatic amylase has lower limits. The range on your own report is what counts.

What is the difference between amylase and pancreatic amylase? Total amylase adds up the amylase from the pancreas and from the salivary glands. Pancreatic amylase measures only the part from the pancreas, which is why its values are lower.

Do I need to fast for an amylase test? It is usually done with your other morning blood tests, fasting. Follow your lab’s instructions.

Amylase or lipase: which is better? For pancreatitis, lipase is more precise and stays high for longer. That is why many doctors order lipase only.

Does Rosa test amylase? No. Rosa measures triglycerides, bilirubin, gamma GT and creatinine, which say a lot about the causes of pancreatitis and about your kidneys. If your doctor wants amylase, they order it separately.

Sources

• Banks and colleagues, classification of acute pancreatitis 2012: revision of the Atlanta classification and definitions by international consensus. Gut, 2013. PMID 23100216
• Tenner and colleagues, American College of Gastroenterology guidelines: management of acute pancreatitis. American Journal of Gastroenterology, 2024. PMID 38857482
• Ismail and Bhayana, lipase or amylase for the diagnosis of acute pancreatitis? Clinical Biochemistry, 2017. PMID 28720341
• Amodio and colleagues, chronic asymptomatic pancreatic hyperenzymemia: a long-term follow-up. Pancreas, 2019. PMID 30946240