Blood Test

AST:ALT Ratio (SGOT/SGPT, De Ritis Ratio)

Name: AST/ALT Ratio (SGOT/SGPT): Normal Range & Liver Disease Pattern
Creator: Suman Konda
Published: 2026-07-05

The ratio of AST to ALT (the De Ritis ratio) is a simple calculation from your liver blood test that helps identify the likely cause of liver damage. An AST:ALT ratio above 2 strongly suggests alcoholic liver disease.¹

Written by Suman Konda, Clinical Pharmacist · Based on peer-reviewed sources · Editorial policy · Not medical advice

Last reviewed and updated: 26 September 2026 · How we check our content

Quick answer

The AST:ALT (De Ritis) ratio divides your AST by your ALT to hint at the cause of liver damage. A ratio above 2 strongly suggests alcoholic liver disease, while a ratio below 1 (ALT dominant) fits viral hepatitis or fatty liver. It is a clue, not a diagnosis, and only means something when the enzymes themselves are raised.

What is the AST:ALT ratio?

AST (aspartate aminotransferase, also called SGOT) and ALT (alanine aminotransferase, also called SGPT) are liver enzymes measured in every liver function test. While both rise when liver cells are damaged, they rise to different degrees depending on the cause. The AST:ALT ratio, also called the De Ritis ratio, is calculated by dividing the AST value by the ALT value. The pattern of which enzyme rises more provides a diagnostic clue to the underlying cause of liver damage.

AST:ALT ratio interpretation

Ratio	Pattern	Likely diagnosis
< 1 (ALT > AST)	ALT dominant	Viral hepatitis (A, B, C), NAFLD/fatty liver, drug-induced liver injury
1:1	Equal rise	Non-specific: less diagnostic value
> 2:1 (AST 2x ALT)	AST dominant	Alcoholic liver disease (classic pattern)
> 3:1	Strongly AST dominant	Alcoholic hepatitis or cirrhosis; consider Wilson disease
Very high ALT (10x+), any ratio	Massive elevation	Acute viral hepatitis, ischaemic hepatitis, drug toxicity

Key points

The AST:ALT (De Ritis) ratio is calculated by dividing the AST value by the ALT value.
A ratio above 2 with raised enzymes strongly suggests alcoholic liver disease.
A ratio below 1 (ALT higher than AST) is typical of viral hepatitis and fatty liver (NAFLD).
Very high ALT (10 times normal or more), at any ratio, points to acute viral hepatitis, ischaemic hepatitis or drug toxicity.
Alcohol damages mitochondria, where AST is concentrated, and depletes the vitamin B6 needed to make ALT; together this explains the AST-heavy pattern.
ALT is more liver-specific than AST, which also comes from heart and muscle, so strenuous exercise or muscle injury can skew the ratio.

Why is AST:ALT >2 typical of alcoholic liver disease?

In alcoholic liver disease, alcohol and its metabolite acetaldehyde directly damage mitochondria (where AST is concentrated in liver cells), causing disproportionate AST release. Simultaneously, alcohol depletes pyridoxal-5-phosphate (vitamin B6), which is required for ALT synthesis: so ALT levels are relatively suppressed. This two-part mechanism explains why AST rises more than ALT in alcoholic liver injury.

Why is ALT higher than AST in viral hepatitis and fatty liver?

In viral hepatitis and NAFLD, hepatocyte cell membrane damage is the primary mechanism, and ALT is predominantly cytoplasmic (released easily through the damaged membrane). ALT is also more specific to the liver than AST (which also comes from heart, muscle and other tissues). So in non-alcoholic liver disease, ALT is the more sensitive and more elevated marker.

Other tests to interpret alongside the ratio

Test	Why it matters
GGT	Very high in alcoholic liver disease; supports AST:ALT >2 pattern
MCV (mean cell volume)	High MCV (macrocytosis) is common with alcohol excess
Bilirubin	Indicates severity of liver dysfunction
Albumin / INR	Liver synthetic function: low = serious

Questions to ask your doctor

What is likely causing my liver enzyme elevation?
Do I need a hepatitis B and C test?
Should I have a liver ultrasound?
Is alcohol use contributing to my liver results?
Do I need a liver biopsy?

AST:ALT ratio at a glance: the compiled numbers

The ratio is simple arithmetic — AST divided by ALT — but the numbers behind it matter. Here are the typical pieces, compiled from standard adult reference intervals:

Measure	Typical adult reference range*	What moves it most
ALT (SGPT)	Roughly 7–56 U/L	Liver cell injury — the most liver-specific of the two
AST (SGOT)	Roughly 10–40 U/L	Liver, but also heart muscle, skeletal muscle and red blood cells
AST:ALT ratio	Usually below 1	A ratio above 2, in the right clinical context, is the classic pattern discussed with alcohol-related liver injury — but it never proves a cause on its own
Typical LFT panel cost	&rupee;500–&rupee;1,000	Both enzymes come inside the panel; standalone, each is typically &rupee;300–&rupee;600

*Ranges vary between labs and analysers — the interval printed on your own report is the one that governs. Prices are approximate bands and vary by city and lab.

AST:ALT myths vs facts

The De Ritis ratio invites more overconfident reading than almost any liver number. Here is what it can and cannot tell you:

MYTH A ratio above 2 proves alcoholic liver disease.

Fact: It suggests it — in the right clinical setting — but it proves nothing by itself. The ratio is one pattern among many, and doctors weigh it against the history, examination and the rest of the liver panel before drawing conclusions.

MYTH AST is just as liver-specific as ALT.

Fact: AST lives in heart muscle, skeletal muscle and red blood cells too. A hard workout, a muscle injury or even a difficult blood draw can raise AST while the liver is perfectly fine — which is exactly why the ratio exists.

MYTH A slightly raised ALT always means liver damage.

Fact: Mild ALT bumps are common and often transient — medicines, recent illness, fatty liver and even day-to-day variation all play a part. Doctors look at the trend and the context, not a single borderline value.

MYTH You must fast before an ALT/AST test.

Fact: Fasting is not generally required for these enzymes. What matters more is avoiding strenuous exercise for a day or two before the draw, since muscle exertion can raise AST and muddy the ratio.

What matters most with your AST:ALT result

The absolute values come first. A ratio calculated from two normal numbers means little; a ratio from markedly raised enzymes means much more. Read the enzymes before the ratio.
AST has non-liver sources. Recent exercise, muscle injury or statin-related muscle effects can all lift AST — mention them so the ratio is read in context.
The trend beats the snapshot. Enzymes moving down on repeat testing is reassuring whatever the ratio; enzymes climbing deserves attention.
The ratio never stands alone. It is one line in the liver panel, read alongside bilirubin, albumin, ALP and GGT — and alongside you. Discuss the full picture with your doctor.

Frequently Asked Questions

What is a normal AST:ALT ratio?

In healthy people the ratio is usually below 1, meaning ALT is equal to or higher than AST. A ratio above 2 — AST more than twice ALT — is the classic pattern of alcohol-related liver injury, while very high ALT with any ratio suggests acute viral or drug-related injury. Your doctor reads the ratio together with the absolute values.

Can exercise raise AST?

Yes. Strenuous exercise and muscle injury release AST from muscle tissue, which can push the ratio up and mimic a liver pattern. For the most meaningful result, avoid intense workouts for a couple of days before the test and tell the lab about any muscle injury.

My ALT is slightly high but my AST is normal. Should I worry?

A mildly raised ALT on its own most commonly reflects fatty liver, especially with extra weight, high triglycerides, or blood sugar issues. It is usually a signal to address lifestyle rather than an emergency — but it does deserve follow-up, so discuss an ultrasound and metabolic checks with your doctor.

Do I need to fast before an ALT/AST test?

Fasting is not usually required for ALT and AST themselves, but they are often ordered as part of a liver panel alongside tests that do need fasting, like glucose or triglycerides. Follow whatever instructions your lab gives for the full panel.

How much does an AST/ALT ratio test cost in India?

There is usually no separate charge for the ratio itself — it is calculated from your AST (SGOT) and ALT (SGPT) values, which are part of a liver function test (LFT). An LFT panel typically costs ₹500–₹1,000 in India, though prices vary by city and lab. Discuss the result with your doctor.

Pharmacist's practical notes

The ratio is only as honest as its two ingredients. Because AST rises with muscle exertion, a ratio drawn the morning after a hard workout or a muscle injury can mislead — if you exercise regularly, mention it when the blood is drawn. Several common medicines can also nudge these enzymes, so bring your medication list to the discussion.

There is no separate charge for the ratio itself: it is arithmetic done on your AST and ALT values, which arrive inside a liver function panel typically costing &rupee;500–&rupee;1,000. Paying for a “ratio test” on its own is unnecessary.

In India

Indian labs report ALT and AST in U/L; older reports may say SGPT/SGOT — the same enzymes. The pair usually comes inside a liver function panel costing roughly &rupee;500–&rupee;1,000; standalone, each is typically &rupee;300–&rupee;600, though prices vary by city and lab.

Where possible, choose a NABL-accredited lab. Reference ranges differ slightly between analysers, so the range printed on your own report is the one that rules.

References

Sources cited on this page. PubMed links open the original abstract.

Dufour DR, Lott JA, Nolte FS, Gretch DR, Koff RS, Seeff LB. Diagnosis and monitoring of hepatic injury. I. Performance characteristics of laboratory tests. Clin Chem. 2000;46(12):2027–2049. PMID 11106349 · doi:10.1093/clinchem/46.12.2027
Sulava E, McQuilkin P, Benson J. Elevated Liver Enzymes: Emergency Department-Focused Management. J Emerg Med. 2017;52(5):654–667. PMID 27889359 · doi:10.1016/j.jemermed.2016.10.016
Korman JD, Volenberg I, Balko J, et al. Screening for Wilson Disease in Acute Liver Failure: A Comparison of Currently Available Diagnostic Tests. Hepatology. 2008;48(4):1167–1174. PMID 18798336 · doi:10.1002/hep.22446

What ALT and AST each measure

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are intracellular enzymes that leak into the bloodstream when liver cells (hepatocytes) are damaged. They are the primary markers of hepatocellular (liver cell) injury, distinct from biliary markers (ALP, GGT) and synthetic function markers (albumin, INR).

ALT (alanine aminotransferase): Found predominantly in the liver. Highly liver-specific, a raised ALT almost always indicates liver cell injury. Normal range: approximately 7–40 IU/L (laboratory-dependent).
AST (aspartate aminotransferase): Found in liver, cardiac muscle, skeletal muscle, kidney, and red blood cells. Less liver-specific than ALT, raised AST without raised ALT is often from muscle rather than liver. Normal range: approximately 10–40 IU/L.

Both enzymes are released in proportion to the degree of hepatocyte death, enzyme levels in the thousands indicate massive liver necrosis (as in paracetamol overdose or ischaemic hepatitis); levels in the tens to low hundreds are typical of chronic hepatitis or NAFLD.²

The AST:ALT ratio, a diagnostic clue

The ratio of AST to ALT (De Ritis ratio) provides an important clinical signal:

AST:ALT below 1 (ALT predominates): Typical of viral hepatitis (hepatitis B and C), non-alcoholic fatty liver disease (NAFLD), and drug-induced liver injury. The liver is damaged but alcohol is not the cause.
AST:ALT ratio 1–2: Overlapping causes, could be alcohol, NASH, or other hepatocellular injury.
AST:ALT above 2 (often above 3): Strongly suggests alcoholic liver disease (alcoholic hepatitis). The mechanism: alcohol depletes pyridoxal phosphate (vitamin B6, an ALT cofactor) and simultaneously upregulates AST synthesis. This biochemical footprint is sufficiently specific that an AST:ALT ratio above 2 in a person with heavy alcohol use is often treated as diagnostic of alcoholic hepatitis without liver biopsy.
AST:ALT above 3 with very elevated AST, normal or mildly elevated ALT: Consider rhabdomyolysis (muscle breakdown releasing AST into blood) or cardiac muscle injury (myocardial infarction, cardiac troponin is the preferred test but AST was historically used before troponin was available).
AST:ALT above 2.2 in acute liver failure: Raises suspicion for fulminant Wilson disease. In one comparison of diagnostic tests in acute liver failure, an AST:ALT ratio above 2.2 identified Wilson disease with 94% sensitivity and 86% specificity, and an alkaline phosphatase to total bilirubin ratio below 4 was even more discriminating (94% sensitivity, 96% specificity), both more useful in this emergency setting than ceruloplasmin, which can be falsely normal in acute liver failure.³

Degree of elevation and what it implies

The magnitude of ALT/AST elevation correlates with acuity and severity of liver injury:

Mild elevation (1–3× upper limit of normal): Non-specific; found in NAFLD, medications, thyroid disease, coeliac disease, vigorous exercise
Moderate elevation (3–10× ULN): Significant hepatocellular injury, viral hepatitis, alcoholic hepatitis, drug toxicity
Severe elevation (above 10× ULN): Acute liver injury, paracetamol overdose, ischaemic hepatitis, autoimmune hepatitis, acute viral hepatitis
Massively elevated (above 100× ULN, ALT in thousands): Acute liver necrosis, typically paracetamol overdose, ischaemic hepatitis, Budd-Chiari syndrome (hepatic vein thrombosis)

Medical Disclaimer: This page is for general educational purposes only and does not constitute medical advice. Always consult a qualified doctor for diagnosis and treatment decisions.