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Blood Test: Alanine Aminotransferase (ALT, or SGPT)

What Is a Blood Test?


What Is an ALT Test?

An ALT test measures the level of alanine aminotransferase, also called ALT or SGPT. ALT is one of the enzymes that help the liver convert food into energy. High levels of these enzymes can be a sign that the liver is injured or irritated, and the enzymes are leaking out of the liver cells.

Why Are ALT Tests Done?

An ALT test may be done if a child has signs of a possible problem with the liver, such as jaundice (yellowish skin or eyes), dark urine, nausea, vomiting, or belly pain. It also might be done if a child is on medicine that makes high liver enzyme levels more likely.

How Should We Prepare for an ALT Test?

Your child may be asked to stop eating and drinking for 8 to 12 hours before the ALT test. Tell your doctor about any medicines your child takes because some drugs might affect the test results.


How Is an ALT Test Done?


  • clean the skin 
  • pull the blood sample into a vial or syringe





Can I Stay With My Child During an ALT Test?


How Long Does an ALT Test Take?


What Happens After an ALT Test?


When Are ALT Test Results Ready?


Are There Any Risks From ALT Tests?



If you have questions about the ALT test, speak with your doctor or the health professional doing the blood draw.