What are Liver Function tests?

Liver function tests (LFTs) are a group of tests used to assess the health of liver. These tests help determine the functioning capability of your liver. The levels of various enzymes and proteins, such as bilirubin, albumin, alkaline phosphatase (ALP), aspartate transaminase (AST), alanine transaminase (ALT) and gamma-glutamyl transpeptidase (GGT), produced by the liver can be measured using LFTs.

These test help measure the amount of damage that has occurred in the liver and to diagnose various liver diseases, such as cirrhosis and hepatitis. In addition, LFTs can help evaluate an ongoing infection or inflammation in the liver or detect any obstruction in blood flow through the liver.

You can take this test if you experience symptoms of liver diseases, or as a part of your regular health check-up.

Commonly performed LFTs are as follows:

  • Liver enzyme test
    • ALT, AST, ALP and GGT tests are used to measure the respective enzyme levels in blood. High levels of ALT and AST can be an indication of liver damage, and high levels of ALP and GGT indicate liver and bile duct damage.
  • Liver protein test
    • Total protein test measures the amount of protein in your blood.
    • Globulin test measures the globulin level in your blood. Low levels can be seen in case of liver damage.
    • Albumin test evaluates the working of your liver in terms of production of proteins needed for the body. Low levels signify liver damage.
    • Prothrombin test measures the time of blood clotting. A longer than usual clotting time is seen in cases of liver damage.
  • Bilirubin test
    • Bilirubin is a yellow fluid that is released in the body when erythrocytes (red blood cells) are broken down. A bilirubin test measures the level of bilirubin in blood. In cases of liver damage, bilirubin is released from the liver, which causes yellow colouration of skin or eyes (jaundice). Bilirubin  is also excreted in urine, giving it a paler colour.
  1. Why are Liver function tests (LFTs) performed?
  2. How do you prepare for Liver function tests (LFTs)?
  3. How are Liver function tests (LFTs) performed?
  4. What do Liver function test (LFT) results indicate?

LFTs can be performed periodically to assess how well your liver is working. Alternatively, they can be done in case of liver diseases or risk of liver diseases or when you experience symptoms related to liver disease.

LFTs are recommended in patients who

  • Have liver disease/damage
  • Are at the risk of hepatitis virus infection
  • Are chronic drinkers
  • Have a family history of liver disease
  • Take drugs that can damage the liver

LFTs are performed in patients who have the following symptoms:

myUpchar doctors after many years of research have created myUpchar Ayurveda Yakritas Capsule by using 100% original and pure herbs of Ayurveda. This Ayurvedic medicine has been recommended by our doctors to lakhs of people for liver-related problems (fatty liver, weakness in the digestive system) with good results.
liver detox tablets
₹899  ₹999  10% OFF

No special preparation is needed for these tests.

However, you need to avoid some medications and foods that could affect the level of proteins and enzymes in your blood. Also, a half-sleeve shirt is preferred for easy collection of blood.

To perform this test, your healthcare provider will first clean the site of blood collection, ie, your arm with an antiseptic solution. Then, a needle will be inserted into a vein in the arm to draw a sample of blood. The collected sample will be sent to a laboratory for further investigation.

Milk Thistle Capsule
₹749  ₹899  16% OFF

Different LFTs can provide different information about your liver function. However, each test result is not an indication of a specific liver condition, but their combined results could be a sign of liver damage.

LFTs can give the following results:

  • Normal: In case of normal test result, you do not need any further investigation.
  • Abnormal: In case of an abnormal test result, it is necessary to know the actual cause of changes. Additional tests are recommended for an accurate understanding of the underlying cause.

However, in some cases, LFTs show altered results due to conditions that affect your bones or some other part of your body. Also, there can be an abnormality even though you do not have any signs. It is best to check in with a doctor to get the correct diagnosis.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. This information is purely from an educational perspective and is in no way a substitute for medical advice from a qualified doctor. 


  1. National Institute of Health. US National Library of Medicine [internet]: Bethesda (MA), US. US Department of Health and Human Services Liver Function Test
  2. National Health Call Center Network: Healthdirect Australia [internet]. Council of Australian Governments; Liver function tests
  3. MedlinePlus Medical Encyclopedia: US National Library of Medicine; Liver Function Tests
  4. American Liver Foundation [internet]. New York (NY): American Association for the Study of Liver Diseases; Liver Function Tests
  5. Better health channel. Department of Health and Human Services [internet]. State government of Victoria; Liver
  6. Lab Tests Online-Au; Australasian Association of Clinical Biochemist; Liver function tests

Related Articles

Upper GI Endoscopy

Dr. Ayush Pandey
MBBS,PG Diploma
7 Years of Experience

Obesity Profile

Dr. Ayush Pandey
MBBS,PG Diploma
7 Years of Experience

Extractable Nuclear Antigen ...

Dr. Ayush Pandey
MBBS,PG Diploma
7 Years of Experience
Read on app
Ask your health query from live doctors now!