Description

The ALT blood test measures the level of alanine transaminase, an enzyme found mainly in the liver. ALT is released into the bloodstream when liver cells are damaged, making this test a useful tool to detect liver injury or disease.

Why the ALT Test Is Important

Your liver performs many vital functions, including producing bile, which helps digest fats and absorb nutrients. Measuring ALT levels can help:

  • Detect liver damage caused by disease, medications, or injury
  • Evaluate liver function as part of routine health screenings
  • Determine the underlying cause of abnormal liver tests
  • Monitor liver health in patients with known liver conditions

The ALT test is often included in a Comprehensive Metabolic Panel (CMP) or ordered individually as an initial screen for liver disease.

Fasting: Not required.