C-reactive protein, serum concentration
This test measures the level of C-reactive protein in your blood, a protein produced by your liver in response to inflammation or infection.
["CRP helps doctors track inflammation, infections, or other health issues."]
Key facts at a glance
- LOINC
- 47098-9
- Short code
- Cr Fld-sCnc
- Synonyms
- Cr Fld-sCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 86430
- 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 a CRP test to check for signs of inflammation, monitor conditions like heart disease, autoimmune disorders, or infections, or evaluate how well you’re responding to treatment. It can also help identify risks for conditions like rheumatoid arthritis or certain types of cancer.
What to Expect Before the Test
No special preparation is needed. You may have a small needle inserted into your arm to draw blood. If you’re on blood thinners, let your provider know beforehand. Avoid strenuous activity or eating heavy meals 24 hours before the test if instructed.
What Happens During the Test?
A healthcare professional will clean your arm with an antiseptic and insert a needle to collect a small amount of blood from your vein. The blood is then sent to a lab for analysis. The process usually takes a few minutes, and you may feel a brief pinch or discomfort.
What Are the Results Measured Against?
CRP levels vary depending on your health and medical history. Higher-than-normal levels may indicate inflammation, infections, or other health concerns, while lower levels suggest minimal inflammation. Your provider will interpret the results in the context of your overall health.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
CRP is a marker for inflammation, often used to assess risk for cardiovascular diseases, infections, or autoimmune conditions. Elevated CRP levels may signal an ongoing inflammatory process, prompting further evaluation or treatment adjustments. It’s also useful for monitoring chronic conditions like arthritis or heart disease.
Short name
CRP
Frequently asked questions
What Does a High CRP Level Mean?
What Does a Low CRP Level Mean?
Can I Eat or Drink Before the Test?
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