Aspartate Transferase (AST)

Who performs an AST blood test?

A phlebotomist usually performs blood draws, including those for an AST blood test, but any healthcare provider who is trained in drawing blood can perform this task. They then send the samples to a lab where a medical laboratory scientist prepares the samples and performs the tests on machines known as analyzers.

Do I need to fast for an AST blood test?

If your AST test is part of a comprehensive metabolic panel (CMP), you’ll likely need to fast for 10 to 12 hours before your CMP blood test. Fasting means not eating or drinking anything other than water.

It’s not as common, but if you’re only getting an AST blood test or a hepatic function panel (HFP), you don’t need to fast.

In any case, your healthcare provider will give you instructions when they order the bloodwork. Be sure to follow their directions.

Do I need to do anything to prepare for an AST blood test?

Many different types of medications and supplements can affect your AST levels, so it’s important to tell your healthcare provider about any drugs or dietary supplements you’re taking before you get the test. In some cases, your healthcare provider may have you stop taking a medication before the test. Only stop taking medication if your healthcare provider tells you to do so.

What should I expect during my AST blood test?

You can expect the following during an AST blood test:

• You’ll sit in a chair, and your healthcare provider will check your arms for an easily accessible vein. This is usually in the inner part of your arm on the other side of your elbow.
• Once they’ve located a vein, they’ll clean and disinfect the area.
• They’ll then insert a small needle into your vein to take a blood sample. This may feel like a small pinch.
• After they insert the needle, a small amount of blood will collect in a test tube.
• Once they have enough blood to test, they’ll remove the needle and hold a cotton ball or gauze on the site to stop the bleeding.
• They’ll place a bandage over the site, and you’ll be finished.

The entire procedure usually takes fewer than five minutes.

What should I expect after my AST blood test?

After your healthcare provider has collected your blood sample, they’ll send it to a laboratory for testing. Once the test results are back, your healthcare provider will share the results with you.

What are the risks of an AST blood test?

Blood tests are a very common and essential part of medical testing and screening. There’s very little risk to having blood tests. You may have slight tenderness or a bruise at the site of the blood draw, but this usually resolves quickly.

When can I expect the results of my AST blood test?

In most cases, you should have your test results within one to two business days, though it could take longer.

What do the results of an AST blood test mean?

Blood test reports, including aspartate transferase (AST) test reports, usually provide the following information:

• The name of the blood test or what was measured in your blood.
• The number or measurement of your blood test result.
• The normal measurement range for that test.
• Information that indicates if your result is normal or abnormal or high or low.

What is the normal range for an AST blood test?

The normal range for aspartate transferase (AST) varies from laboratory to laboratory. One common reference range for an AST blood test is 8 to 33 U/L (units per liter). As ranges can vary depending on the laboratory, it’s important to check your test result report to see what your specific lab’s reference range is.

It’s also important to know that there’s no AST range that’s normal for all people. A healthy AST level can change depending on several factors, including:

• Your age.
• Your sex.
• Your race.
• Your weight.

Your healthcare provider will consider all these factors when interpreting your test result.

What does it mean if my AST level is high?

An elevated AST level may be a sign of a liver condition. Liver disease is even more likely when the results of other liver blood tests are also abnormal. Although it’s not as common, elevated AST levels can be caused by cell damage in other areas of your body as well.

A high AST level may indicate any of the following liver conditions:

• Alcohol-induced liver injury.
• Hepatitis (liver inflammation).
• Cirrhosis (scarring of the liver).
• Taking medications that are toxic to your liver.
• Liver tumor or liver cancer.
• Liver ischemia (not enough blood flow to your liver, which leads to death of liver tissue).

A high AST level may also indicate any of the following conditions that aren’t directly related to your liver:

• Hemochromatosis (having too much iron in your body, which damages your heart, liver and pancreas).
• Heart attack (myocardial infarction).
• Mononucleosis (“mono”).
• Muscle disease.
• Pancreatitis.

Your AST levels can also increase temporarily after the following events:

• Deep burns.
• Seizure.
• Heart procedures.
• Surgery.
• Intense exercise.

You may also have increased levels of AST if you’re pregnant.

It’s important to understand that having a high AST test result does not necessarily mean you have a medical condition. Other factors can affect your AST levels. Your healthcare provider will consider several factors, including other blood test results and your medical history, when analyzing your results.

Should I be worried if I have a high AST test result?

If your AST test result is higher than the given normal range on your report, it doesn’t necessarily mean that you have a medical condition that needs treatment. People with healthy and proper liver function can have an AST level outside of the normal range, which can happen due to several factors, including:

• Your age.
• Your sex.
• Your race.
• Your diet.
• Exercise.
• Taking medications that can affect your AST levels.
• If you’re pregnant.

Your healthcare provider will take into consideration all these factors, including your other blood test results, when analyzing your AST levels and will let you know if you should undergo further testing.

Do I need follow-up tests if my AST results are abnormal?

Your healthcare provider may recommend follow-up tests if you have an abnormal AST level. Follow-up testing may include:

• Repeat AST blood tests.
• Other blood tests.
• Imaging tests.
• A biopsy.

When should I call my doctor?

If you’re experiencing symptoms of liver damage, such as jaundice or belly pain, call your healthcare provider.

If you’ve been diagnosed with a liver condition and are experiencing new or concerning symptoms, contact your healthcare provider.

If you have any questions about your aspartate transaminase (AST) results, don’t be afraid to ask your healthcare provider questions.