Urea blood test in Chiswick

What the test measures

When the body breaks down protein from food or from its own tissues, it produces ammonia. The liver turns this into urea, which is less harmful, and the kidneys filter urea out of the blood into the urine. Measuring urea in the blood therefore gives information about kidney filtration, hydration and protein breakdown all at once.

Because so many things influence it, urea is rarely read alone. It is part of the standard urea and electrolytes check, together with sodium, potassium and creatinine, and is often compared with creatinine and eGFR to help work out whether a change is linked to the kidneys themselves or to hydration and diet.

Your price includes the sample taken at our Chiswick clinic, analysis at the Randox accredited laboratory, a practitioner review of your result and a GP feedback report on request. No GP referral is needed.

Who it is for

• You have high blood pressure, diabetes or a family history of kidney disease.
• You take medicines that can affect the kidneys, such as anti-inflammatory painkillers or diuretics.
• You have had a spell of vomiting, diarrhoea or poor fluid intake and want to check your recovery.
• You follow a high-protein diet or train intensively and want a baseline.
• Your GP has asked you to monitor your kidney function.

Understanding your result

A raised urea is most often due to dehydration, a high-protein diet, intense exercise or bleeding in the upper gut, and it can also reflect reduced kidney function. Certain medicines, including steroids, can raise it too. A low urea can be seen with a low-protein diet, pregnancy, over-hydration and, less often, liver conditions. Your practitioner will look at urea alongside creatinine and eGFR to understand the pattern.

Your report shows the laboratory reference range. A result outside it is a prompt for discussion with your practitioner, not a diagnosis. If you notice black, tarry stools or are vomiting blood, seek urgent medical care.

Preparing for your test

You do not need to fast, but avoid an unusually large high-protein meal in the hours before your sample. Drink water as normal so you are neither dehydrated nor overloaded with fluid, and avoid hard training the day before. Keep taking your medicines and tell us about them, especially anti-inflammatory painkillers, diuretics and blood pressure tablets.

Urea is part of the Kidney Health Check, which also includes creatinine, eGFR and electrolytes, and of the Standard Screen. You can also browse every blood test and price in Chiswick.

Questions

How much is a urea blood test in Chiswick?

The urea test costs £59. This includes your sample at our clinic, laboratory analysis, a practitioner review and a GP feedback report on request.

Can dehydration raise my urea?

Yes. When you are short of fluid the kidneys conserve water, and urea in the blood rises. This often corrects once you are drinking normally.

Is urea or creatinine the better kidney test?

Creatinine and eGFR are the main measures of kidney filtration. Urea adds useful context about hydration and protein breakdown, so they are best read together.

Does a high-protein diet affect the result?

It can. More protein means more urea is made, which can push the level towards the top of the range or above it.