ALT Blood Test


What is an ALT Blood Test?

The ALT blood test, also known as an alanine transaminase test, is a type of liver function test used to diagnose liver damage and/or disease. ALT is an enzyme found mostly in the liver and when cells in the liver are damaged, ALT is released into the blood.

Preparation for ALT Blood Test

Most of the time no specific preparation is necessary prior to having an ALT blood test, but your doctor or laboratory may give you specific instructions if they require any test preparation.

Procedure for ALT Blood Test

A blood sample is used for an ALT test. A healthcare provider will draw the blood from a vein in your arm and send it to a lab for evaluation.

Types of ALT Blood Test

  • ALT Total Test: measures the total ALT enzyme levels in the blood.
  • ALT (SGPT) Test: measures the ALT enzymes produced by the liver.

Risks of AT Blood Test

An ALT blood test is typically a low-risk procedure. The most common risk associated with a blood test is slight bleeding at the puncture site and/or feeling faint or dizzy after donation.

Why Do Healthcare Providers Request an ALT Blood Test?

ALT blood tests are typically requested when a person has signs or symptoms of a potential liver disorder such as jaundice, abdominal pain, vomiting, or fatigue.

When is an ALT Blood Test Ordered?

In general, healthcare providers will order an ALT blood test when they suspect a person may have hepatitis, an enlarged liver, abscesses, or other liver diseases. In some cases, healthcare providers may routinely order ALT blood tests during routine labwork or monitoring of chronic liver conditions.

How Is an ALT Blood Test Results Interpreted?

Normal ranges for ALT levels vary by age, gender, and overall health. Generally, normal ALT levels range from 7-56 units per liter (U/L). An ALT test result that is outside the normal parameters may indicate liver damage, inflammation, or disease.