C-Reactive Protein (CRP) Test Test
A C-reactive protein (CRP) test measures the level of CRP in your blood. High levels can mean you have inflammation in your body, which may be caused by an infection, autoimmune disorder, or other condition.
What this test measures
A C-reactive protein test measures the level of C-reactive protein (CRP) in a sample of your blood. Your liver makes CRP in response to inflammation.
What your results mean
Reference ranges vary by laboratory and by your age and sex. MedlinePlus does not publish a single normal range for this test — always read your result against the range printed on your own lab report and discuss it with your provider.
Higher-than-normal results
High CRP levels may mean you have an acute or chronic health condition, such as infections, inflammatory bowel disease, autoimmune disorders, lung diseases, or exposure to smoking or environmental toxins.
Frequently asked questions
What does a CRP test measure?
It measures the level of C-reactive protein in your blood, which is made by the liver in response to inflammation.
What is considered a normal CRP level?
According to MedlinePlus, a value of 0.8-1.0 mg/dL or lower is thought to be a healthy amount.
What can cause high CRP levels besides inflammation?
High CRP can also be linked to insomnia, depression, hormone replacement therapy, obesity, and sex (females often have slightly higher levels).
Does a high CRP test tell me what is causing the inflammation?
No, it tells you how much inflammation you have, but not what's causing it or where it is.
How will my provider use my CRP results?
Your provider will look at your CRP results along with other tests, your symptoms, and medical history to make a diagnosis.
Related lab tests
Sources
- MedlinePlus: C-Reactive Protein (CRP) Test — NIH MedlinePlus
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.