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C-reactive protein (CRP) in plasma

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

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

Quick summary

["CRP helps assess inflammation, often used to monitor conditions like infections or autoimmune diseases."]

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

Key facts at a glance

LOINC
99095-2
Short code
S pyo DNA CSF Ql NAA+probe
Synonyms
S pyo DNA CSF Ql NAA+probe
Category
coagulation
Sample
csf
Container
Sterile tube
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
probe-amp-tar
Specimen volume
1-2 mL
Stability
Immediate analysis required, Refrigerated: 1h
Hemolysis max
200
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Your healthcare provider may order this test to check for signs of inflammation, infections, or other health conditions such as heart disease, arthritis, or certain types of cancer. It can also be used to monitor treatment progress for conditions like rheumatoid arthritis or lupus.

What to Expect During the Test

A small amount of blood is drawn from a vein, usually in your arm. You may feel a slight pinch, but it should only take a few minutes. You can usually return to normal activities right after.

Possible Preparations

No special preparation is needed for this test. However, if you are on certain medications or have specific health conditions, inform your healthcare provider before the test.

What the Results Mean

Higher CRP levels often indicate inflammation. While reference ranges can vary, elevated levels may suggest infections, autoimmune diseases, or other inflammatory conditions. Your results will be interpreted by your healthcare provider in the context of your overall health.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

CRP (Plasma)

Frequently asked questions

What Are Common Causes of Elevated CRP?
Elevated CRP levels can be caused by infections (like pneumonia or urinary tract infections), inflammatory diseases (such as rheumatoid arthritis or lupus), heart disease, certain cancers, or other conditions that trigger an inflammatory response. Chronic conditions like obesity or metabolic syndrome may also be associated with higher CRP levels.
What Are Common Causes of Normal or Low CRP?
CRP levels can be normal or low in people without active inflammation. This could include those with stable chronic conditions, those who have recently recovered from an infection, or individuals with no known inflammatory diseases. However, low CRP alone does not rule out inflammation in some cases.
How Often Should CRP Be Monitored?
CRP testing frequency depends on your health condition and treatment plan. Your healthcare provider will determine how often to check CRP levels based on your specific situation, such as monitoring chronic diseases, response to treatment, or detecting early signs of inflammation.
  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