ALT · high result
High ALT levels: what they mean, causes and what to check next
Short answer
ALT is the most liver-specific of the routine enzymes, so a high value means liver cells are irritated or injured. On most lab ranges that is above about 40–55 U/L, though the American College of Gastroenterology uses tighter healthy limits of 33 U/L for men and 25 for women. Mild elevations — up to two or three times the upper limit — are most often fatty liver, alcohol, a medication or supplement, or recent hard exercise; three to ten times points to viral hepatitis or drug injury; above ten times is acute hepatitis, a blocked bile duct, acetaminophen toxicity or a circulation problem. The first step for a mild, symptom-free elevation is a repeat with the full liver panel in two to four weeks.
Medically reviewed by Youmna DiStefano, MD · Last reviewed November 2026
When does this result need same-day care?
- ALT more than ten times the upper limit (roughly above 400–500 U/L), or any level with jaundice, confusion, severe abdominal pain, vomiting or easy bruising — same-day or emergency care
- Any ALT rise after an acetaminophen overdose or regular use above 3–4 g a day — emergency care; the antidote works best early
- Rising values on repeat together with a falling albumin or platelet count, or a prolonged clotting time — prompt specialist review
What is the normal range for ALT?
- Male, age 18+: 7.00 – 55.0 U/L
- Female, age 18+: 7.00 – 45.0 U/L
Often reflects fatty liver, alcohol use, viral hepatitis, or muscle injury. Some medications also raise ALT.
Full reference table, citations and testing options: ALT biomarker page.
What are the common causes of high ALT?
- Fatty liver disease (metabolic dysfunction-associated steatotic liver disease) — the most common cause in the US, tied to weight, insulin resistance and triglycerides; ALT is usually higher than AST
- Alcohol — AST tends to run higher than ALT (often a 2:1 ratio) and GGT is raised
- Medications — statins, acetaminophen above 2–3 g a day, amoxicillin-clavulanate and other antibiotics, anti-seizure drugs, methotrexate, isoniazid, anabolic steroids; usually within weeks of starting
- Supplements — green tea extract, kava, high-dose turmeric, bodybuilding and weight-loss products, kratom; a frequent and under-reported cause
- Viral hepatitis — hepatitis B and C (often silent for years), hepatitis A and E, and mononucleosis or CMV infection
- Strenuous exercise or muscle injury in the previous few days — muscle releases ALT and AST, with creatine kinase also raised
- Hemochromatosis, autoimmune hepatitis, Wilson disease (under 40), alpha-1 antitrypsin deficiency, celiac disease and thyroid disease
- Gallstones or bile duct obstruction (alkaline phosphatase and bilirubin rise too), and heart failure or a period of low blood pressure that starves the liver of blood (very high, short-lived values)
What symptoms go with high ALT?
- Usually none — most high ALT values are found on routine blood work
- Fatigue, nausea, discomfort under the right ribs
- Yellowing of the skin or eyes, dark urine, pale stools, itching when the injury is more significant
- Confusion, easy bruising or bleeding, abdominal swelling in severe or long-standing liver disease
What do clinicians usually check next?
- Repeat with the full liver panel — AST, alkaline phosphatase, GGT, bilirubin, albumin — plus platelets, in 2–4 weeks, after three days without alcohol or hard exercise
- Hepatitis B surface antigen and core antibody, and hepatitis C antibody
- Ferritin with transferrin saturation (hemochromatosis), A1c and lipids (metabolic), celiac antibodies, TSH
- A complete inventory of medications, supplements, herbal products and alcohol, with the start dates alongside the dates of the blood tests
- Liver ultrasound for fat, gallstones and bile duct size; a FIB-4 score (age, AST, ALT, platelets) to estimate fibrosis risk, with elastography when it is indeterminate or high
- If still unexplained: autoimmune markers (ANA, smooth muscle antibody, IgG), ceruloplasmin in anyone under 40, alpha-1 antitrypsin level
- Weight loss of 7–10%, stopping alcohol and the suspected supplement, and a repeat in 8–12 weeks — most mild elevations resolve with this
Follow-up tests available at TestWell: TSH Test (Thyroid Stimulating Hormone) ($20.99), TSH with Reflex to Free T4 Test ($29.99), TSH + Free T4 Test ($27.99), Ferritin Test ($21.99), Transferrin Test ($23.99), GGT Test (Gamma-Glutamyl Transferase) ($19.99).
How do you recheck ALT?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| ALT Test (Alanine Aminotransferase) | Test | $16.99 | No | 1–3 business days |
Common questions
What ALT level is concerning?
Above the reference range (roughly 40–55 U/L depending on lab and sex, or 33 for men and 25 for women by the stricter ACG limits) warrants a repeat and an explanation; above about three times the upper limit prompts a faster workup; above ten times, or any level with jaundice, needs same-day care.
Is an ALT of 60 serious?
Usually not on its own. It is a mild elevation — the range where fatty liver, alcohol, a medication or recent exercise are the usual explanations. Repeat it with the full liver panel in a few weeks; if it persists, the standard workup above finds the cause in most people.
Can exercise raise ALT?
Yes — muscle releases ALT and AST after hard training, with creatine kinase rising too. Rest 48–72 hours and repeat before concluding anything about the liver.
What does high ALT with a normal AST mean?
An ALT-predominant pattern is typical of fatty liver, medications and viral hepatitis — liver-cell injury rather than alcohol or muscle. AST running higher than ALT, especially about 2:1, points toward alcohol.
How do I lower my ALT?
Treat the cause: for fatty liver, losing 7–10% of body weight, cutting sugar and alcohol and increasing activity lowers ALT within 2–3 months; stopping an offending medication or supplement normalizes it in weeks; viral hepatitis is treated directly. There is no supplement that lowers ALT — several raise it.
Does fatty liver always raise ALT?
No — many people with fatty liver have a normal ALT, which is why a normal result does not exclude it. When ALT is raised in fatty liver it is usually under three times the upper limit, and the FIB-4 score or elastography, not the ALT level, tells you whether scarring is developing.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.