This blood test measures an enzyme called alanine transaminase (ALT). Enzymes are chemicals that help the cells of your body work. ALT is an enzyme made in the liver. It is released into the blood when tissues are damaged.
This enzyme is also called serum glutamic-pyruvic transaminase, or SGPT.
The ALT test checks for and measures damage to the liver. It is also done to check medical treatments that may affect the liver.
Having this test will take just a few minutes. A small amount of blood is taken from a vein in your arm with a needle. The blood is collected in tubes and sent to a lab.
Ask your healthcare provider when and how you will get the result of the test.
Some of the reasons your ALT level may be much higher than normal (up to 50 times the upper limit of normal) are:
Your ALT levels may be higher than normal also if:
No medical problems are known to cause an ALT level that is lower than normal. Sometimes the test result may be lower than normal but it does not mean there is a problem.
Test results are only one part of a larger picture that takes into account your medical history, physical exam, and current health. Sometimes a test needs to be repeated to check the first result. Talk to your healthcare provider about the results and ask questions, such as: