In this video, Dr. Sunil Dargar, MBBS, MD, Pathologist, New Delhi, discusses the relationship between BUN and urea. Urea is a protein waste metabolite with nitrogenous molecule are attached. In urea, the percentage of blood urea nitrogen (BUN) is approximately 48%. If the blood reports shows blood urea is 40, then BUN will be approximately 19-20. Both expresses almost the same thing, as few countries use blood urea or BUN as an expression but few other countries use blood urea as an expression.