Erythrocyte Sedimentation Rate (ESR)

What is Erythrocyte Sedimentation Rate (ESR)?

Erythrocyte sedimentation rate (ESR) is a simple and inexpensive test that measures how quickly red blood cells (erythrocytes) settle in a test tube containing a sample of your blood. It’s commonly measured as part of a comprehensive metabolic panel. In practical terms, a higher ESR indicates the presence of inflammation or infection in your body.


No special preparation is required for ESR testing and the test is usually done as part of a checkup or repeated if your doctor suspects there may be inflammation in your body.


To do the test, a healthcare provider takes a sample of your blood and places it in an evacuated tube. The test tube is then left undisturbed for a period of time, usually 1 hour, and the rate at which the red blood cells settle at the bottom is measured. The result is reported as millimeters per hour (mm/hr).


There are several different types of ESR tests that are used to measure the rate of sedimentation. The most common type is the Westergren method, which measures the sedimentation by observing the height of the sediment when left for a certain period of time. Other variables that are taken into consideration include sample volume, temperature, and time elapsed.


There are no risks associated with ESR testing. The procedure is simple and no blood transfusion or special preparation is necessary.

Why it’s Done

ESR testing is done to help diagnose and monitor inflammation and infection. It’s often used to check for diseases like rheumatoid arthritis, systemic lupus, and angyolysis. It can also be used to monitor the progress of treatment for certain diseases.

When to Get Tested

Your doctor may recommend that you get an ESR test if you’re experiencing symptoms of inflammation or infection. These may include fever, fatigue, joint pain, and swelling. You may also get the test if you’re being treated for a condition that involves inflammation, such as rheumatoid arthritis. The test can be used to help diagnose the condition or to monitor its progress.

Normal Values

  • Women: 0-20 mm/hr
  • Men: 0-15 mm/hr
  • Children: 0-10 mm/hr

Normal values may vary depending on the lab that performs the test. Always consult your healthcare provider for more information.