: Lactate (Lactic Acid), Blood, Mass Concentration

: What Is Lactate?

: Lactate, often called lactic acid, is a chemical your body makes when cells convert glucose into energy, particularly when oxygen is limited. Muscles produce lactate during intense exercise, and the liver normally clears it. A blood lactate test measures how much lactate is circulating in your bloodstream.

: Why the Test Is Ordered

: Doctors order a blood lactate test when they suspect that organs or tissues are not receiving enough oxygen, such as in severe infection, shock, or certain metabolic disorders. It may also be checked during critical illness, after major injury, or when someone has unexplained symptoms like rapid breathing, confusion, or weakness.

: How the Sample Is Collected

: The test is usually done on a blood sample drawn from a vein, and in some settings from an arterial blood sample. A tourniquet may be used briefly, but the sample should be collected and handled promptly because prolonged stasis or delay can affect lactate results. No special preparation is typically required unless your care team gives other instructions.

: Understanding the Results

: A normal lactate level generally indicates that tissues are getting adequate oxygen and that lactate is being cleared normally. Higher-than-expected levels can occur with poor oxygen delivery, strenuous exercise, liver problems, certain medications, or inherited metabolic conditions. Your clinician interprets lactate alongside your symptoms, other lab tests, and the clinical context; a single value is rarely interpreted alone.