Key takeaways
- An LFT checks several enzymes, proteins and bilirubin to assess liver health.
- Fasting for 8-10 hours before the blood draw gives the most reliable results.
- Normal adult ranges are provided as a guide, but each lab may have slightly different limits.
- Abnormal values need a doctor’s interpretation; they do not confirm a disease on their own.
- HWP Diagnostic can collect the sample at home and usually delivers results within 24 hours.
A Liver Function Test (LFT) is a simple blood test that gives your doctor a snapshot of how well your liver is working. The liver carries out hundreds of jobs – from cleaning toxins to making proteins that help your blood clot. Because many conditions can affect the liver, an LFT is one of the first tools used to spot early stress or damage.
What is a Liver Function Test?
The LFT, also called a Liver Panel or Hepatic Function Panel, measures several enzymes, proteins and pigments that the liver produces or clears. By looking at these values together, doctors can see whether the liver is functioning within the usual limits.
Why Might Your Doctor Order an LFT?
- Unexplained abdominal pain, jaundice (yellowing of the skin or eyes), dark urine or pale stools.
- Persistent fatigue that has no clear cause.
- Monitoring a known liver condition such as hepatitis, fatty liver disease or cirrhosis.
- Before starting medicines that are processed by the liver (for example, certain antibiotics, anti-tubercular drugs or cholesterol-lowering tablets).
- As part of a routine pre-surgical assessment.
- Regular alcohol consumption, diabetes, obesity or metabolic syndrome, which can increase the risk of fatty liver.
How to Prepare for the Test
The test requires a small amount of blood, usually drawn from a vein in the arm. To obtain the most reliable numbers, an 8-10 hour fast is recommended. This means no food or drink (except water) during that period. If you are taking regular medicines, keep taking them unless your doctor tells you otherwise.
Tip: HWP Diagnostic provides home blood-sample collection in Malad, Kandivali, Borivali and Goregaon, making fasting easier to manage at home.
What the Test Measures
| Component | What it tells you |
|---|---|
| SGPT / ALT | Enzyme released when liver cells are injured. |
| SGOT / AST | Enzyme found in liver and other organs; high levels may indicate liver or muscle stress. |
| Alkaline Phosphatase (ALP) | Often rises when bile ducts are blocked or in bone disease. |
| Gamma-Glutamyl Transferase (GGT) | Sensitive to alcohol-related liver stress and some medicines. |
| Total / Direct / Indirect Bilirubin | Pigment produced from broken-down red cells; high levels cause jaundice. |
| Total Protein, Albumin, Globulin | Proteins made by the liver; low albumin can suggest chronic liver disease. |
| A/G Ratio | Balance between albumin and globulin; abnormal ratios may hint at liver or immune issues. |
Understanding the Results – Typical Adult Ranges
Reference ranges can vary between laboratories, age groups and the specific method used. The values below are widely accepted for healthy adults; your report will include the range used by the lab that performed the test.
- ALT (SGPT): 7–56 U/L
- AST (SGOT): 10–40 U/L
- ALP: 30–120 U/L
- GGT: 9–48 U/L (men), 8–35 U/L (women)
- Total Bilirubin: 0.3–1.2 mg/dL
- Direct Bilirubin: 0.0–0.3 mg/dL
- Indirect Bilirubin: 0.2–0.8 mg/dL
- Total Protein: 6.0–8.3 g/dL
- Albumin: 3.5–5.0 g/dL
- Globulin: 2.0–3.5 g/dL
- A/G Ratio: 1.1–2.5
If any of these numbers fall outside the stated range, it does not automatically mean you have a disease. Many factors – such as recent exercise, medications, or even a temporary infection – can influence the results. Always discuss the findings with your doctor, who will interpret them in the context of your overall health.
How the Test Is Performed and Reporting
- Sample collection: A trained phlebotomist draws a few millilitres of blood from a vein. With HWP Diagnostic, the sample can be collected at your home and then safely transported to the laboratory.
- Laboratory analysis: The blood is processed using automated chemistry analysers that measure each component.
- Report turnaround: Most common LFTs are ready within 24 hours. The report will list each measured value alongside the laboratory’s reference range and a brief comment if any result is markedly abnormal.
You can view the full list of available tests on our test catalogue or explore comprehensive health checks in our full-body test packages.
When to Consider an LFT
While routine testing is not required for everyone, an LFT becomes useful in the following situations:
- You notice yellowing of the eyes or skin, dark urine, or unusually light-coloured stools.
- You have persistent upper-right abdominal discomfort that does not resolve.
- You are starting a medication known to affect liver metabolism.
- You have risk factors such as heavy alcohol use, type-2 diabetes, obesity or a family history of liver disease.
- Your surgeon asks for a baseline liver assessment before an operation.
If any of these apply, talk to your healthcare provider about whether an LFT is appropriate.
When to Talk to Your Doctor
If you receive an LFT report and:
- One or more values are markedly above or below the normal range.
- You experience new or worsening symptoms such as jaundice, severe fatigue, abdominal pain, or unexplained weight loss.
- You are unsure why the test was ordered or what the results mean.
Prompt discussion helps ensure any underlying issue is investigated early and managed safely.
For appointments, sample-collection requests or any queries, feel free to contact us.
Frequently asked questions
Do I need to fast before a Liver Function Test?
Yes, an 8-10 hour fast is generally recommended to avoid food-related variations in enzyme levels.
Can I take my regular medicines on the day of the test?
Usually you should continue your prescribed medicines unless your doctor tells you otherwise.
How long does it take to get the LFT results?
Most common LFTs are reported within 24 hours after the sample reaches the laboratory.
What does a high ALT level indicate?
A raised ALT suggests liver cell injury, but the cause can range from medication effects to temporary infections; only a doctor can interpret it.
Is a Liver Function Test painful?
The blood draw may cause a brief pinch, but the procedure itself is quick and generally well tolerated.
Can I have the test done at home?
Yes, HWP Diagnostic offers home blood-sample collection in several Mumbai suburbs, making the process convenient.
HWP Diagnostic Editorial Team
Health guides written by the team at HWP Diagnostic, Mumbai, to help you understand your tests before you book. This article is for general education and is not a substitute for medical advice - reference ranges vary between labs, so always discuss your results with your doctor. Read our editorial policy. Photos: Pexels.
