C-reactive protein, serum/plasma concentration
This test measures the level of C-reactive protein, a protein produced by your liver in response to inflammation or infection in your body.
["CRP helps doctors assess inflammation, track infections, or monitor conditions like autoimmune diseases."]
Key facts at a glance
- LOINC
- 36014-9
- Short code
- CT Hip
- Synonyms
- CT Hip
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ct
- 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, monitor chronic conditions like rheumatoid arthritis or lupus, evaluate infections, or assess how well you’re responding to treatment for conditions such as heart disease or kidney problems. It can also be used as part of a general health screening or to monitor recovery after surgery or illness.
What to Expect Before the Test
No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if it’s done on an empty stomach, but this depends on your doctor’s instructions. Bring any medications you’re currently taking, as some may affect your results.
What Happens During the Test?
A small needle will be inserted into your arm or a blood sample will be collected from your finger. The process is quick and typically causes only mild discomfort. The blood sample is then sent to a lab for analysis.
What Happens After the Test?
You can usually return to your normal activities immediately. If you experienced any discomfort, apply a small bandage to the site and keep it clean. Avoid heavy lifting or strenuous activities for a few hours.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated CRP levels often indicate inflammation, which can be caused by infections (such as pneumonia or urinary tract infections), autoimmune diseases (like lupus or rheumatoid arthritis), or other inflammatory conditions. Very high levels may suggest severe infections, heart disease, or other serious health issues. Low or normal levels usually mean there’s little to no inflammation, but this can vary depending on your overall health and medical history. Your doctor will interpret the results in the context of your symptoms and other tests.
Short name
CRP (Serum/Plasma)
Frequently asked questions
How Long Does It Take to Get Results?
What If My Results Are Abnormal?
Can Diet or Medications 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