{"id":"alt","name":"Alanine Aminotransferase (ALT)","shortName":"ALT","aliases":["ALT","SGPT","Alanine Aminotransferase","ALT (SGPT)","GPT","ALAT","Alanine Transaminase","ALT (Alanine Aminotransferase)","TGP","ALT (TGP)","Alanine Aminotransferase (ALT)","Alanine Aminotransferase (ALT/SGPT)","ALT/SGPT","SGPT (ALT)","Serum Glutamic Pyruvic Transaminase","Glutamic Pyruvic Transaminase","Alanine Amino Transferase","ALT, Serum","Alanine Aminotransferase, Serum","GPT (ALT)","ALT/GPT","ALAT (GPT)","GPT/ALAT","Transaminasa Glutámico Pirúvica","Alanin-Aminotransferase","Alanine Aminotransferase Level"],"abbreviations":["ALT","SGPT","GPT","ALAT","TGP"],"loinc":[{"code":"1742-6","primary":true},{"code":"1743-4","primary":false},{"code":"1744-2","primary":false},{"code":"77144-4","primary":false}],"specimen":"serum-or-plasma","units":[{"ucum":"U/L","display":"U/L"},{"ucum":"ukat/L","display":"µkat/L"},{"ucum":"nkat/L","display":"nkat/L"}],"referenceRanges":[{"population":"Men, 18+","low":0,"high":44,"unit":"U/L","unitDisplay":"U/L","note":"Labcorp's interval for men over 17 (printed in IU/L, the same as U/L). It matches the cut-off that 95% of low-risk U.S. men in NHANES fell below (44 U/L, Ruhl and Everhart 2012). Other published intervals differ: Mayo Clinic Laboratories 7-55 U/L (age 1 and older), ABIM 10-40 U/L and MedlinePlus 4-36 U/L. Guidelines also describe a lower healthy limit; see the wellness target.","sources":[{"title":"Pediatric Testing Reference Ranges (ALT (SGPT), test 001545; lists ages 0 to 17 and adults over 17)","url":"https://www.labcorp.com/content/dam/labcorp/drupal/178250_DX_TL_PediatricTestRef_Final.pdf","publisher":"Labcorp"},{"title":"Upper limits of normal for alanine aminotransferase activity in the United States population","url":"https://pubmed.ncbi.nlm.nih.gov/21987480/","publisher":"Hepatology","year":2012},{"title":"Comprehensive Metabolic Panel, Serum (test CMAMA), Mayo Clinic Laboratories Extended Catalog","url":"https://www.testcatalog.org/show/CMAMA","publisher":"Mayo Clinic Laboratories"},{"title":"ABIM Laboratory Test Reference Ranges, January 2026","url":"https://www.abim.org/Media/bfijryql/laboratory-reference-ranges.pdf","publisher":"American Board of Internal Medicine","year":2026},{"title":"ALT blood test (MedlinePlus Medical Encyclopedia)","url":"https://medlineplus.gov/ency/article/003473.htm","publisher":"MedlinePlus, National Library of Medicine"}]},{"population":"Women, 18+","low":0,"high":32,"unit":"U/L","unitDisplay":"U/L","note":"Labcorp's interval for women over 17. It matches the cut-off that 95% of low-risk U.S. women in NHANES fell below (32 U/L, Ruhl and Everhart 2012). Other published intervals differ: Mayo Clinic Laboratories 7-45 U/L (age 1 and older), ABIM 10-40 U/L and MedlinePlus 4-36 U/L.","sources":[{"title":"Pediatric Testing Reference Ranges (ALT (SGPT), test 001545; lists ages 0 to 17 and adults over 17)","url":"https://www.labcorp.com/content/dam/labcorp/drupal/178250_DX_TL_PediatricTestRef_Final.pdf","publisher":"Labcorp"},{"title":"Upper limits of normal for alanine aminotransferase activity in the United States population","url":"https://pubmed.ncbi.nlm.nih.gov/21987480/","publisher":"Hepatology","year":2012},{"title":"Comprehensive Metabolic Panel, Serum (test CMAMA), Mayo Clinic Laboratories Extended Catalog","url":"https://www.testcatalog.org/show/CMAMA","publisher":"Mayo Clinic Laboratories"},{"title":"ABIM Laboratory Test Reference Ranges, January 2026","url":"https://www.abim.org/Media/bfijryql/laboratory-reference-ranges.pdf","publisher":"American Board of Internal Medicine","year":2026},{"title":"ALT blood test (MedlinePlus Medical Encyclopedia)","url":"https://medlineplus.gov/ency/article/003473.htm","publisher":"MedlinePlus, National Library of Medicine"}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"An enzyme made mostly in liver cells. It leaks into the blood when liver cells are irritated or damaged.","url":"https://bloodtesttracker.com/markers/alt","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}