Urea

One of the two waste products the kidneys clear. It also moves with hydration and protein intake, so it is read alongside creatinine rather than on its own.

Urea in the Biomarker Guide — what it is, why it is tested, and what moves the number.

Add-on markers can only be added to venous samples.

Timing

Ideally fasted. Urea falls after eating.

Ideal, not required. Glucose is the only marker we sell that is invalid unfasted. If fasting does not fit your day, take it anyway and do the same next time.

Turnaround: the lab reports this test within 24 hours of receiving your sample, counted in working days. Most samples reach them within about 3 days of posting. Full detail on our Turnaround Times page.

We do not interpret results. Not medical advice or a diagnosis.