What should you know about LDH liver function test?

Lactate dehydrogenase, or LDH, helps cells produce energy. When cells are irritated or injured, LDH can enter the bloodstream. It is not specific to the liver: muscle, blood cells and other organs also contain it. A raised result may therefore reflect several different processes, including liver inflammation, alcohol-related harm, viral hepatitis, strenuous muscle activity or a sample affected by broken blood cells. A result within the laboratory range does not rule out every liver problem.

Your clinician reads LDH with ALT, AST, alkaline phosphatase, bilirubin, albumin and the clinical history. The pattern matters more than one isolated value. Related information may include [Liver Function Test](/treatments/diagnostics-and-screening/liver-function-test/), [Hepatitis A](/conditions/hepatitis-a/) or [Alcohol Use Disorder](/conditions/alcohol-use-disorder/).

Take the report to the clinician who requested it and ask which result pattern they are assessing. Tell them about prescribed medicines, supplements, alcohol intake, recent exercise, infections and any previous liver diagnosis. Do not stop a medicine without advice. Further blood tests, a repeat sample or imaging may be suggested when the finding does not fit the rest of the picture. Avoid self-treating an abnormal result with detox products, which can themselves stress the liver.

Arrange prompt medical review for yellowing of the skin or eyes, dark urine, pale stools, persistent vomiting, increasing abdominal swelling, unusual sleepiness or confusion. Seek emergency help for severe confusion, vomiting blood, black stools, fainting or severe abdominal pain. These symptoms need assessment regardless of whether the LDH result is high, low or still awaiting confirmation.

Ask: Which other liver results change the meaning of my LDH? Could the sample or recent muscle activity have affected it? Do I need a repeat blood test or imaging? Which symptoms should make me seek urgent help? Would testing for [Hepatitis B](/conditions/hepatitis-b/) or [Hepatitis C](/conditions/hepatitis-c/) be relevant?