Erythrocyte Sedimentation Rate (ESR)
The erythrocyte sedimentation rate (ESR), or sedimentation rate (sed rate), is a measure of the settling of red blood cells in a tube of blood during one hour. The rate is an indication of inflammation and increases in many diseases.
The sed rate is a simple blood test. You don't need to fast before the test.
A nurse or medical assistant will use a needle to draw blood from a vein, most likely a vein in your arm. The site on your arm may be tender for a few hours, but you'll be able to resume most normal activities. Results from your sed rate test will be reported in the distance in millimeters (mm) red blood cells have descended in one hour (hr). The normal range is 0-22 mm/hr for men and 0-29 mm/hr for women.