How to know if the BUN and creatinine are elevated due to dehydration

Blood urea nitrogen (BUN) and creatinine are both measures of renal function. When these are elevated, it may be due to renal impairment, but it may also be due to dehydration. How can we tell the difference? Here’s how: Urea and creatinine are filtered by the glomerulus. Urea is partially reabsorbed by the tubules and…