Urea
Serum urea
High
45.6mg·dL⁻¹Ref 15–40 mg·dL⁻¹
Z +2.90↑ Bad

The card shows an example result of 45.6 mg·dL⁻¹, which is 2.90 SD above the mean.

What it measures

Urea is made in the liver from the ammonia left when protein is broken down, and cleared by the kidneys. Some labs report urea and others BUN.

Reference range

FieldValue
AbbreviationUrea
GroupKidney and protein
Unitmg·dL⁻¹
Healthy range15–40
Mean27.5
SD6.25
Direction↑ Bad — a raised value is the concern.

The mean is (low + high) / 2 and the SD is (high − low) / 4, so the healthy range covers Z from −2 to +2.

Reading the result

  • High — Can mean reduced kidney function, dehydration, or a high-protein diet.
  • Low — Not the concern this panel tracks. Low values can come from a low-protein diet or liver disease.

Notes

  • To turn urea into BUN, multiply by 0.467.
  • This page is general information, not medical advice. Discuss results with a clinician.