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Total C-Reactive Protein (CRP) Concentration

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

This test measures the level of C-reactive protein in your blood, a protein produced by your liver in response to inflammation or infection.

Quick summary

["CRP helps doctors track inflammation, infection, or other health issues."]

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

Key facts at a glance

LOINC
39545-9
Short code
Crab IgE/IgE total %
Synonyms
Crab IgE/IgE total %
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
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?

Your healthcare provider may order this test to check for signs of inflammation, infection, or other conditions like autoimmune diseases, heart disease, or after surgery. It can also help monitor treatment progress for certain conditions.

What Does a High or Low CRP Level Mean?

A higher CRP level often indicates inflammation or infection. A lower level may suggest reduced inflammation, but it doesn’t always mean you’re healthy. Results can vary based on your overall health and medical history.

How Is This Test Performed?

A small blood sample is taken from a vein in your arm. The blood is then sent to a lab where it is analyzed to measure CRP levels using a sensitive detection method.

What Should You Expect Before or After the Test?

You may feel slight discomfort or bruising at the injection site, but most people don’t experience significant pain. Avoid vigorous activity for a few hours after the test to prevent bleeding.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Total CRP

Frequently asked questions

What Are Common Causes of Elevated CRP Levels?
Elevated CRP levels can be caused by infections (like pneumonia or urinary tract infections), injuries, surgeries, autoimmune diseases (like rheumatoid arthritis), or other inflammatory conditions.
Can CRP Levels Be Affected by Medications?
Yes, some medications, such as steroids or nonsteroidal anti-inflammatory drugs (NSAIDs), can lower CRP levels. Always discuss your medications with your healthcare provider.
How Often Should CRP Be Monitored?
Your healthcare provider will determine how often to check CRP levels based on your medical needs. Some patients need it more frequently if they have ongoing inflammation or chronic conditions.
  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