Liver Function Test(LFT)

LFT stands for liver function tests, a panel of blood tests measuring liver enzymes (ALT, AST, ALP, GGT), bilirubin, albumin and clotting (prothrombin time). They assess liver cell injury, bile flow and the liver’s synthetic ability. LFTs help diagnose, stage and monitor liver disease or medication effects; abnormal results require clinical correlation and further evaluation.

A normal liver function panel includes typical reference ranges: ALT 7–56 U/L, AST 10–40 U/L, alkaline phosphatase 44–147 U/L, gamma‑GT about 9–48 U/L, total bilirubin 0.1–1.2 mg/dL, and albumin 3.5–5.0 g/dL. Prothrombin time/INR is usually about 11–13.5 seconds (INR 0.8–1.2). Ranges vary by lab, age, sex and clinical context—interpret with your clinician.

A liver function test in pregnancy is a blood panel measuring enzymes and proteins — typically ALT, AST, alkaline phosphatase, GGT, bilirubin and albumin — to assess maternal liver health. It detects pregnancy-related problems (intrahepatic cholestasis, preeclampsia/HELLP) and other liver disease. Results are interpreted with normal pregnancy-related changes in mind; testing is done for symptoms or risk factors.

Four warning signs of liver damage are: 1) Jaundice — yellowing of the skin and eyes; 2) Persistent abdominal pain or swelling, especially in the upper right side or with fluid buildup; 3) Unexplained fatigue, weakness, or confusion; 4) Easy bruising or bleeding, and changes in urine/stool color (dark urine, pale stools) indicating impaired bile processing.

A bad LFT result shows abnormal liver enzyme or function markers: significantly raised ALT and AST (hepatocellular injury), high ALP and GGT (cholestasis), elevated bilirubin (jaundice risk), low albumin and prolonged prothrombin time (reduced synthetic function). Severity depends on how far values deviate, their pattern and trends; marked or worsening abnormalities warrant urgent clinical assessment to identify causes and guide treatment.

Most liver function tests (ALT, AST, ALP, GGT, bilirubin, albumin) do not require fasting. However, labs may ask for an 8–12 hour fast if LFTs are ordered alongside lipid or glucose tests or if your clinician requests it. Avoid alcohol for 24–48 hours beforehand and tell staff about medications and supplements, as these can affect results.