It is so because the level of blood urea partly depends on external factors like the diet and medications of the patient. Out of the two, creatinine tests are generally more reliable. However, in chronic kidney diseases and in patients who are in long term dialysis, these two tests can together reflect the status of GFR accurately. In earlier stages of kidney disease, the test results of BUN and creatinine levels may not show much variation while the GFR continuously falls to about 50% of normal value. The relationship of creatinine and urea blood levels with GFR is very complex. This filtration rate, popularly known as Glomerular Filtration Rate, varies with age, sex, health status, progression of kidney disease etc. Urea and creatinine levels are measured to assess the filtration rate of the kidney. The end goal of dialysis is a healthy and, if possible, a happy patient.

So, for example, if the BUN test value of a patient is 12mg/dl, it means that urea level is around 24.5mg/dl. The amount of urea is approximately double the nitrogen estimated from the BUN test. The BUN test measures this nitrogen from the blood. One of the constituents of urea is nitrogen. Since ammonia is very toxic if present in blood, our liver converts ammonia into urea. When proteins in the body are broken down, ammonia is released. Blood urea level can change with age, health status, dietary intake, medicine intake, etc. The value has a wide range because it depends on many external factors.

The normal range of blood urea level in India can be interpreted from the table below: Through this article, I will discuss common questions and their answers regarding BUN. It is generally noticed that both of these- the blood creatinine and blood urea levels increase and decrease proportionally in a given patient. Blood urea level and creatinine are two important factors that help in knowing the kidney function and the degree and severity of kidney disease. Before starting dialysis, the doctor assesses the kidney function.

Bun creatinine levels normal range