Can this result diagnose a condition on its own?

No. Laboratory results are interpreted with symptoms, medical history, specimen conditions and related tests.

Which reference range should I use?

Start with the performing laboratory's own reference interval; clinical cutoffs, when relevant, are separate sourced thresholds used for a specific purpose.

When should I discuss the result with a healthcare professional?

Results that are clearly outside range, persistent, symptomatic or unexpected should be reviewed by a healthcare professional. If you have emergency symptoms such as chest pain, severe shortness of breath, fainting, new neurologic symptoms or severe illness, seek urgent assessment rather than waiting for a laboratory result.

Information about a laboratory test

Lactate: What Does This Test Measure?

The Lactate test measures the level of lactate produced during energy metabolism, which can provide context about tissue perfusion, oxygen use and metabolic stress.

Test summary

Test name: Lactate
Abbreviations: Lactate, Lactic acid
Category: Metabolic / Perfusion Markers
Panel: Acute Illness / Perfusion Assessment
Specimen: Whole blood / plasma
Common units: mmol/L, mg/dL

What does the test measure?

The Lactate test measures the level of lactate produced during energy metabolism, which can provide context about tissue perfusion, oxygen use and metabolic stress.

Why is the test ordered?

It may be ordered in severe illness to provide information about tissue perfusion and metabolic stress, for example during assessment of shock or sepsis.

Information about a low result

A low value is usually not interpreted as a clinical problem by itself; the purpose of testing and laboratory context matter.

Information about a high result

High lactate can occur for many reasons, including reduced tissue perfusion, severe infection or sepsis, shock, seizures, intense exercise, liver dysfunction and certain medicines.

Reference and clinical context

Start with the performing laboratory's reference interval, unit, specimen type and method. Numeric information on this page is stored as sourced example intervals or clinical thresholds.

Reference ranges may vary by laboratory, method used, age, sex, pregnancy status, and clinical context. The reference range on your own laboratory report takes precedence.

Interpretation notes

Lactate can change rapidly and is sensitive to specimen collection and processing. In severe illness, clinical status and change on serial measurements may be more informative than one value.

Related specialties

Emergency Medicine
Internal Medicine
Infectious Diseases
Cardiology

Frequently asked questions

More information about this test

Lactate: High Result: What Does It Mean?

Sources

Procalcitonin Test — U.S. National Library of Medicine (MedlinePlus)
Government medical reference · 2025 · Procalcitonin, systemic bacterial infection and sepsis context · Verified: Aug 12, 2026
Lactate Test — U.S. National Library of Medicine (MedlinePlus)
Government medical reference · 2024 · Lactate testing in perfusion, hypoxia and severe-illness contexts · Verified: Aug 12, 2026