All tests › Blood gases

Lactate

Blood gases · also printed as Blood lactate, Lactic acid, Serum lactate, Plasma lactate, Lactate (blood gas)

Typical UK adult range0.5 to 2.0 mmol/L

Ranges vary between laboratories; the range printed on the report takes precedence.

What this test measures

Lactate is produced when muscles and other tissues work without enough oxygen, or when the liver cannot clear it. It is a marker of how well the tissues are being supplied.

Why doctors request it

Used in hospital to judge how unwell someone is with infection, poor circulation or after a seizure, and followed to see the response to treatment.

What commonly pushes it up

Exercise, including struggling against a tourniquet
Severe infection or poor circulation
Seizures
Liver disease
Some medicines as a class, for example metformin in kidney failure
Some inherited conditions

What commonly pushes it down

There is no meaningful low value

Everyday reasons for a value outside the range

A tight tourniquet or a hard-to-draw sample raises it
Recent exercise raises it

About the sample

Analysed quickly; venous and arterial values are similar.

Written by a UK consultant physician. Typical UK adult reference ranges; your laboratory's own printed range takes precedence.

Got a report with Lactate on it?

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This is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.