What Are Normal Levels of Urea and Creatinine in the Blood?

Urea and creatinine are two important waste products found in your blood. They are measured through routine blood tests to help evaluate how well your kidneys are working. If your kidneys are healthy, they filter out these substances and remove them from the body through urine. When kidney function slows down, urea and creatinine levels can rise.

Normal levels of urea, often reported as blood urea nitrogen (BUN), usually fall within the range of:

• 7 to 20 mg/dL (milligrams per deciliter)

BUN levels can vary depending on how much protein you eat, how hydrated you are, and whether you are taking certain medications. A slightly high or low level is not always a cause for concern, but a consistently elevated BUN may signal reduced kidney function or dehydration.

Normal levels of creatinine in the blood are:

• 0.6 to 1.2 mg/dL for men
• 0.5 to 1.1 mg/dL for women

Creatinine is produced by muscle metabolism and cleared by the kidneys. Unlike BUN, creatinine is less affected by diet, which makes it a more stable indicator of kidney health. When creatinine levels are higher than normal, it may mean your kidneys are not filtering as well as they should.

Doctors often use both urea and creatinine levels together to get a clearer picture of kidney function. They may also calculate the BUN-to-creatinine ratio to help understand whether a problem is related to the kidneys or another cause, such as dehydration.

Knowing your urea and creatinine levels can provide early clues about how your kidneys are doing, even before symptoms appear. These values are simple but powerful tools in keeping your health on track.

Looking for more questions?

Visit our Kidney Questions page for all other topics explained in plain language.