Educational information only. At Precursor, blood testing is requested and reviewed by a clinician and considered alongside your history and other markers, not as a stand-alone diagnosis. Testing is performed in NATA-accredited laboratories to ISO 15189 standards.

What is urea?

Urea is a waste product formed when the body breaks down protein. It is made in the liver and removed by the kidneys, so its level in the blood reflects a mix of protein intake, hydration and kidney function. It is a long-standing companion to creatinine in assessing the kidneys.

Why it matters

Urea adds context to creatinine and eGFR. Because it is sensitive to hydration and protein intake as well as kidney filtering, the relationship between urea and creatinine can help a clinician tell dehydration apart from a kidney-specific issue.

What your results can mean

If your result is higher

A raised urea can reflect dehydration, a high-protein intake, or reduced kidney clearance. Its meaning becomes clearer when read against creatinine and your hydration status.

If your result is within the reference range

A urea in range, alongside a normal creatinine and eGFR, is reassuring for kidney function and hydration.

Australian reporting and interpretation

Urea is reported in millimoles per litre (mmol/L). The RCPA adult guide interval is 3.0 to 10.0 mmol/L and may vary with age, sex and laboratory method. Hydration, protein intake and kidney function all affect the result, so read it with creatinine, eGFR and the range on your report.

Test your kidney health with Precursor

Urea is most informative alongside creatinine and eGFR. At Precursor it is measured as part of Full Advanced Bloods, a single clinician-reviewed blood draw covering your kidney, heart, metabolic, hormonal, liver, thyroid and nutrient markers together, giving you and your clinician a broad baseline to understand and track.