The C-reactive protein (CRP) blood test measures the level of CRP in the blood. CRP is a protein produced by the liver in response to inflammation in the body. The test is often used to help diagnose or monitor inflammatory conditions, such as infections, autoimmune diseases, and cardiovascular disease.

The CRP blood test is a simple procedure that involves taking a small sample of blood from a vein in the arm. The sample is then sent to a laboratory for analysis. Results are usually available within a day or two.

The normal range for CRP levels in the blood is less than 10 milligrams per liter (mg/L). Elevated levels of CRP in the blood may indicate inflammation in the body, but cannot pinpoint the exact location or cause of the inflammation.

In general, higher levels of CRP in the blood are associated with a higher risk of cardiovascular disease, including heart attack and stroke. High CRP levels may also be associated with other conditions, such as rheumatoid arthritis, inflammatory bowel disease, and some types of cancer.

A CRP blood test can be used to monitor the progression of certain diseases or to determine the effectiveness of treatment. For example, a decrease in CRP levels over time may indicate that treatment is working, while an increase in CRP levels may indicate that the disease is progressing or that treatment needs to be adjusted.

In summary, the CRP blood test is a simple and useful tool for diagnosing and monitoring inflammatory conditions, including cardiovascular disease. If you have symptoms of inflammation or are at risk of developing a disease associated with elevated CRP levels, talk to your healthcare provider about whether a CRP blood test may be appropriate for you.