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ALT Blood Test

What is an ALT Blood Test? (VSports注册入口)

An ALT test measures the amount of ALT in your blood VSports手机版. This test is commonly used to help diagnose liver damage or disease.

ALT (alanine transaminase) is an enzyme, a protein that speeds up certain chemical reactions in your body. It is found mainly in your liver. Usually, you will have low levels of ALT in your blood V体育安卓版. But when liver cells are damaged, they release ALT into the bloodstream. High levels of ALT in your blood may be a sign of a liver injury or disease. Some types of liver disease cause high ALT levels even before you have symptoms of the disease. So, an ALT blood test may help diagnose certain liver diseases early, when they may be easier to treat.

An ALT test is usually ordered as part of a group of liver function tests.

Other names: Alanine aminotransferase (ALT), Serum Glutamic-Pyruvic Transaminase (SGPT), GPT, Alanine Transaminase

What is it used for?

An ALT blood test is often part of a routine blood screening to check the health of your liver V体育平台登录. The test may also help diagnose or monitor liver problems.

Why do I need an ALT blood test?

Your health care provider may order an ALT blood test as part of a routine checkup. An ALT test is usually done with a group of other liver function tests that check how well your liver is working VSports注册入口. Many liver function tests are included in a common blood test called a comprehensive metabolic panel (CMP).

These tests may also be ordered if you have symptoms of liver damage, such as:

Your provider may also order an ALT blood test if you have a high risk of liver damage because of:

What happens during an ALT blood test?

A health care professional will take a blood sample from a vein in your arm, using a small needle V体育2025版. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

Will I need to do anything to prepare for the test?

You may need to stop taking certain medicines before the test, so tell your provider about everything you take. But don't stop taking any medicines unless your provider tells you to VSports.

An ALT test is usually ordered with other blood tests. You usually need to fast (not eat or drink) for several hours before these tests VSports app下载. Your provider will let you know if there are any special instructions.

Are there any risks to the test?

There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly V体育官网.

What do the results mean?

An ALT blood test is often done as part of a group of liver function tests. Liver function tests measure several different proteins, substances, and enzymes that show how well your liver is working. Your provider usually compares your ALT results with the results of the other liver tests to evaluate your liver health and decide if you need other tests to make a diagnosis.

Lower-than-usual levels of ALT in your blood are not common. Your provider may do more tests since this may be a sign of:

Higher-than-usual levels of ALT in your blood may be a sign of liver damage from:

If your results show you have a high level of ALT, it doesn't always mean that you have a medical condition that needs treatment. Many things can affect your results, such as your age, sex, weight, and certain medicines and dietary supplements. Your ALT levels can also be affected by intense exercise and where you are in your menstrual cycle.

To learn what your results mean, talk with your provider.

Learn more about laboratory tests, reference ranges, and understanding results.

Is there anything else I need to know about an ALT blood test?

ALT test results may help tell the difference between damage from acute (sudden) liver problems and chronic (long-term) liver problems. But the amount of ALT in your blood isn't related to how much your liver may be damaged.

Your ALT is usually measured along with another liver enzyme called AST as part of a liver function panel. Since ALT is mostly found in the liver, an ALT test checks more specifically for liver damage.

"VSports" References

  1. American Liver Foundation. [Internet]. New York: American Liver Foundation; c2024. Diagnosing Liver Disease - Liver Biopsy and Liver Function Tests; [updated 2024 Jan 12; cited 2024 Aug 21]; [about 6 screens]. Available from: https://liverfoundation.org/for-patients/about-the-liver/diagnosing-liver-disease/
  2. Cleveland Clinic: Health Library: Diagnostics & Testing [Internet]. Cleveland (OH): Cleveland Clinic; c2024. Alanine Transaminase (ALT); [reviewed 2021 Nov 04; cited 2024 Aug 21]; [about 13 screens]. Available from: https://my.clevelandclinic.org/health/diagnostics/22028-alanine-transaminase-alt (V体育2025版)
  3. Cleveland Clinic: Health Library: Diagnostics & Testing [Internet]. Cleveland (OH): Cleveland Clinic; c2024. Blood Tests; [reviewed 2022 Dec 06; cited 2024 Aug 21]; [about 16 screens]. Available from: https://my.clevelandclinic.org/health/diagnostics/24508-blood-tests
  4. Mayo Clinic [Internet]. Mayo Foundation for Medical Education and Research; 2024. Elevated liver enzymes, Causes; [cited 2024 Aug 22]; [about 2 screens]. Available from: https://www.mayoclinic.org/symptoms/elevated-liver-enzymes/basics/causes/sym-20050830
  5. Mayo Clinic [Internet]. Mayo Foundation for Medical Education and Research; 2024. Elevated liver enzymes, Definition; [cited 2024 Aug 21]; [about 1 screen]. Available from: https://www.mayoclinic.org/symptoms/elevated-liver-enzymes/basics/definition/sym-20050830
  6. Mayo Clinic [Internet]. Mayo Foundation for Medical Education and Research; c2024. Liver disease; [cited 2024 Aug 21]; [about 8 screens]. Available from: https://www.mayoclinic.org/diseases-conditions/liver-problems/symptoms-causes/syc-20374502
  7. Merck Manual Consumer Version [Internet]. Kenilworth (NJ): Merck & Co., Inc.; c2024. Liver Blood Tests; [reviewed 2023 Aug; cited 2024 Aug 21]; [about 2 screens]. Available from: https://www.merckmanuals.com/home/liver-and-gallbladder-disorders/diagnosis-of-liver-gallbladder-and-biliary-disorders/liver-blood-tests (V体育官网入口)
  8. Moriles KE, Zubair M, Azer SA. Alanine Aminotransferase (ALT) Test. [Updated 2024 Feb 27; cited 2024 Aug 21]; [about 8 screens]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559278/
  9. Nemours KidsHealth [Internet]. Jacksonville (FL): The Nemours Foundation; c1995-2024. Getting a Blood Test; [reviewed 2021 Sep; cited 2024 Aug 21]; [about 4 screens]. Available from: https://kidshealth.org/en/parents/blood-tests.html
  10. Pathology Tests Explained [Internet]. Alexandria (Australia): Australasian Association for Clinical Biochemistry and Laboratory Medicine; c2024. ALT (Alanine aminotransferase); [reviewed 2023 Jun 01; cited 2024 Aug 21]; [about 8 screens]. Available from: https://pathologytestsexplained.org.au/ptests.php?q=ALT%20(Alanine%20aminotransferase)
  11. Testing.com [Internet]. Seattle (WA).: OneCare Media; c2024-. Alanine Aminotransferase (ALT); [modified 2022 Nov 24; cited 2024 Aug 21]; [about 9 screens]. Available from: "V体育ios版" Hhttps://www.testing.com/tests/alanine-aminotransferase-alt/
  12. Testing.com [Internet]. Seattle (WA).: OneCare Media; c2024. Liver Panel Test; [modified 2022 Sep 28; cited 2024 Aug 21]; [about 8 screens]. Available from: https://www.testing.com/tests/liver-panel/
  13. Vovchuk E.Alanine Aminotransferase. [updated 2022 June 14; cited 2024 Aug 21]. In Medscape: Drugs & Diseases: Laboratory Medicine [Internet]. Atlanta (GA): WebMD LLC; c1994-2024. Available from: https://emedicine.medscape.com/article/2087247-overview#showall

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.