How you prepare

Very strenuous exercise, such as intense weight training or a very long run, can cause sudden increases in your CRP level. Your doctor may tell you to avoid such activities before your test.

If your blood sample will be used for additional tests, you may need to avoid eating or drinking for a certain amount of time before the test. For example, if you're having an hs-CRP test to check for heart disease, your doctor is likely to order a cholesterol test at the same time.

Your doctor or nurse will give you specific instructions on how to prepare for your test.

Some medications can affect your CRP level. Always tell your doctor about the medications you take, including those bought without a prescription.