C-reactive protein (CRP) mass concentration
This test measures the amount of C-reactive protein in your blood, a protein produced by your liver in response to inflammation.
["CRP helps doctors assess inflammation, often used to monitor conditions like infections or autoimmune diseases."]
Key facts at a glance
- LOINC
- 28406-7
- Short code
- LOSSOFINDEPENDENCE
- Synonyms
- —
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- reported-living-hiv
- 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 CRP Matters in Your Health
CRP is a marker for inflammation, which your body produces as a defense against injury, infection, or illness. High levels may signal an active inflammatory process, such as an infection, injury, or certain diseases like rheumatoid arthritis or heart disease. Your doctor may order this test to check for inflammation or to monitor treatment progress.
When You Might Need This Test
Your doctor might recommend a CRP test if you have symptoms of inflammation (like fever, pain, or swelling), if you have a known condition linked to inflammation, or if you’re recovering from surgery, an infection, or a medical procedure. It can also be used to track how well a treatment is working.
What to Expect Before the Test
This test is usually done by drawing blood from a vein in your arm. You may feel a slight pinch, but it’s quick and painless. No special preparation is needed unless your doctor instructs otherwise. Avoid strenuous activity or eating heavy meals 24 hours before the test if directed.
What the Results Mean
Results are interpreted based on your overall health and symptoms. Very low levels may indicate no active inflammation, while higher levels could point to an underlying issue. Your doctor will discuss the results with you in the context of your medical history and other test results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
CRP is a key tool for diagnosing and managing conditions involving inflammation. It helps doctors distinguish between infections, autoimmune diseases, and other inflammatory conditions. Elevated CRP levels can also signal risks for heart disease or other chronic inflammatory disorders, prompting further evaluation or treatment adjustments.
Short name
CRP
Frequently asked questions
What causes CRP levels to be high?
How often should I get this test?
Can diet or lifestyle affect CRP levels?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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