Skip to content

Lactate concentration in fluid (e.g., serum/plasma)

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of lactate, a substance produced when your body breaks down sugar for energy, often in fluids like blood.

Quick summary

["Lactate helps assess how well your body is using oxygen and can signal potential health issues."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
55931-0
Short code
Lactate Dial fld-sCnc
Synonyms
Lactate Dial fld-sCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Critical range
— – 4 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Doctors may order lactate tests to check for conditions like low blood oxygen, shock, heart problems, or infections. It can also help monitor people with severe illnesses or during surgery.

What to Expect Before the Test

You’ll likely have a small needle inserted into your arm or vein to draw blood. If you’re in a hospital, they may check lactate levels in your bloodstream more often during treatment.

What the Results Mean

Higher-than-normal lactate levels may indicate poor oxygen use, which can happen in emergencies like heart attacks, severe infections, or dehydration. Lower levels might suggest overuse of sugar for energy, though this is rare.

Common Conditions Monitored

Lactate tests are often used in critical care settings to track responses to treatments for conditions like sepsis, heart failure, or trauma.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: Lactate is a marker for tissue hypoxia (low oxygen) and metabolic stress. Elevated levels can signal urgent medical needs, such as shock or organ dysfunction, prompting faster interventions.

Short name

Lactate Level

Frequently asked questions

How often is this test repeated?
If you have a serious illness or condition, your doctor may order this test multiple times, especially if you’re in the hospital or receiving intensive care.
What does a normal result mean?
A normal result doesn’t guarantee you’re healthy, but it suggests your body is using oxygen efficiently. Your doctor will interpret results based on your overall health and symptoms.
Can I eat or drink before this test?
You may need to fast for a few hours before blood is drawn, but your doctor will give specific instructions based on your situation.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy