Blood Urea Nitrogen

BUN (Blood Urea Nitrogen), BUN:Creatinine Ratio, Urea Nitrogen, Blood

Why It Is Done

A blood urea nitrogen (BUN) test is done to:

• See if your kidneys are working normally.
• See if your kidney disease is getting worse.
• See if treatment of your kidney disease is working.
• See if severe dehydration is present. Dehydration generally causes BUN levels to rise more than creatinine levels. This causes a high BUN-to-creatinine ratio. Kidney disease or blockage of the flow of urine from your kidney causes both BUN and creatinine levels to go up.

Go to previous section	Go to top of page	Go to next section
Author:	Jan Nissl, RN, BS	Last Updated: August 21, 2006
Medical Review:	Patrice Burgess, MD - Family Medicine
© 1995-2008 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.