Sedimentation Rate: About This Test

What is it?

The sedimentation rate (sed rate) test is a blood test. It measures how quickly red blood cells settle in a test tube. When there's inflammation in the body, the red blood cells stick together and fall more quickly than normal to the bottom of the tube.

Why is this test done?

A sed rate test is done to:

• Find out if inflammation is present.

• Check on the progress of a disease.

• See how well a treatment is working.

How do you prepare for the test?

In general, there's nothing you have to do before this test, unless your doctor tells you to.

How is the test done?

A health professional uses a needle to take a blood sample, usually from the arm.

How long does the test take?

The test will take a few minutes.

What happens after the test?

• You will probably be able to go home right away.

• You can go back to your usual activities right away.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.

Current as of: May 13, 2023

Content Version: 14.0

Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.