C-reactive protein (CRP) – Serum/Plasma Concentration

Why It’s Done

Your healthcare provider may order this test to check for signs of inflammation, monitor chronic conditions (such as arthritis or heart disease), or evaluate responses to treatments. It can also help identify infections or other inflammatory processes in your body.

What to Expect Before the Test

No special preparation is needed, but you may be asked to fast for 8–12 hours before the test if it’s part of a broader metabolic or liver evaluation. Avoid strenuous activity 24 hours before testing.

A small needle will be inserted into your arm or vein to draw blood. You may feel a brief pinch, but it usually takes only a few minutes. The blood sample is then sent to a lab for analysis.

You can resume normal activities immediately. There may be mild bruising or soreness at the injection site, which usually fades within a day or two. If you experience excessive bleeding or pain, contact your provider.

CRP levels vary depending on your health status. Higher than expected levels may indicate inflammation, infections, or certain autoimmune disorders. Your doctor will interpret the results in the context of your medical history and other tests.

Higher CRP levels might suggest conditions like rheumatoid arthritis, heart disease, or an active infection. Lower levels could indicate no significant inflammation, but this isn’t always definitive on its own.