Kidney
Why This Kidney Test Matters
This kidney blood test at home service uses a professional venous blood sample to assess key markers of kidney function – including eGFR, creatinine and urea – so you can see how well your kidneys are filtering waste and protecting your long‑term health.
What Is Chronic Kidney Disease And How Is It Detected?
Chronic kidney disease (CKD) is a long-term condition where your kidneys gradually lose their ability to filter waste products from your blood. Unlike acute kidney injury, which happens suddenly, CKD develops slowly over months or years – often with no symptoms until kidney function is significantly reduced.
Your kidneys are responsible for removing toxins, balancing fluid levels, regulating blood pressure, and maintaining appropriate levels of minerals and electrolytes for the proper function of your heart and muscles. When kidney function declines, waste products such as creatinine and urea begin to accumulate in the bloodstream, and the body struggles to maintain the delicate balance it requires.
CKD affects millions of people in the UK, and many don’t know they have it. High blood pressure, type 2 diabetes, obesity, smoking, and a family history of kidney problems are among the most common risk factors.
Because early-stage CKD rarely causes noticeable symptoms, blood tests are the only reliable way to catch it before serious complications develop.
How Kidney Function Is Measured
The key marker used to assess kidney function is estimated glomerular filtration rate (eGFR). This measures how well the kidneys filter blood and is expressed as mL/min/1.73 m². A healthy eGFR is typically 90 or above, but levels can decline with age or kidney damage.
UK guidance uses eGFR to classify CKD into five stages:
- Stage 1 (eGFR 90+): Normal or high kidney function, but other signs of kidney damage may be present
- Stage 2 (eGFR 60–89): Mildly reduced function with other signs of kidney damage
- Stage 3a (eGFR 45–59): Mild to moderate reduction in kidney function
- Stage 3b (eGFR 30–44): Moderate to severe decrease in kidney function
- Stage 4 (eGFR 15–29): Severe decrease in kidney function
- Stage 5 (eGFR below 15): Kidney failure requiring dialysis or transplant
Your kidney function test also measures creatinine (a waste product of muscle breakdown) and urea (a waste product of protein breakdown). Elevated levels of either can indicate that your kidneys aren’t clearing waste efficiently.
Only a healthcare professional who knows your complete medical history can diagnose CKD or determine its stage. This test provides information to support an informed conversation with your GP or specialist about your kidney health and next steps.
Protect Your Kidneys Before It’s Too Late: At-Home Blood Test for Silent Health Risks
Your kidneys work tirelessly behind the scenes – filtering waste, balancing fluids, and keeping you going.
But factors like high blood pressure, diabetes, or smoking can damage them silently, with no warnings until serious issues like fatigue, swelling, or disease strike. Don’t risk it. Our at-home kidney blood test checks key functions, giving you peace of mind and the data to make changes now.
Why Act Today?
Thousands of proactive Brits have uncovered hidden risks early, avoiding bigger problems. Get accurate results from a professional nurse visit – your first step to stronger health.
The Silent Struggle of Your Kidneys – Why Early Checks Are Essential
Your kidneys are powerhouse filters, removing waste, regulating blood pressure, and maintaining electrolytes for heart and muscle health. But when they’re strained – from obesity, excess alcohol, medications, or conditions like heart disease – damage builds quietly. No symptoms mean you might not notice until advanced stages, leading to chronic kidney disease (CKD) that affects millions.
The stakes? Untreated issues can cause exhaustion, high BP spikes, or even dialysis. If you’re older, have diabetes, or a family history, your risks are higher. Regular testing isn’t optional – it’s your best defense, empowering small lifestyle tweaks to keep your kidneys thriving.
Are Kidney Risks Hiding in Your Routine? Spot the Warning Signs
Kidney problems don’t announce themselves – but red flags can appear. Ask yourself:
- Do you have high blood pressure, diabetes, or heart disease?
- Smoking, excess alcohol, or frequent medication use in your habits?
- Older age, obesity, or family history of kidney issues?
- Subtle symptoms like persistent fatigue, swelling in legs/ankles, or changes in urination?
These aren’t coincidences – they could signal strain on your kidneys. Ignoring them invites regret, but knowledge lets you intervene early and reclaim control.
Simple Ways to Support Your Kidney Health – And Prevent Future Problems
The good news? Kidney function can often improve with targeted changes. Use your test results to guide:
- Hydration Focus: Drink plenty of water to flush waste and ease urea/creatinine buildup.
- Diet Adjustments: Cut salt and processed foods to lower BP and support electrolyte balance.
- Lifestyle Shifts: Quit smoking, limit alcohol, manage weight, and monitor conditions like diabetes.
- Routine Monitoring: Retest annually or after changes – share with your GP for expert advice.
Our customers feel empowered:
“This test caught my early risks – now my levels are stable, and I feel great!” – David R., Leeds.
Biomarkers Covered (Focused on Kidney Function):
- Urea: Waste from protein breakdown; high levels may signal kidney issues, low ones dehydration.
- Estimated Glomerular Filtration Rate (eGFR): Measures how well your kidneys filter blood – the gold standard for overall function.
- Creatinine: Muscle waste product cleared by kidneys; elevated levels can indicate problems, adjusted for muscle mass.
Overcome Your Doubts – We’re Here to Help
- Worried About Symptoms? This test catches issues before they show, ideal for high-risk lifestyles.
- Is It Accurate? Nurse-led draws and accredited labs ensure top-tier reliability – trusted by 10,000+.
- Too Much Hassle? We bring the expertise to your door – no travel, no stress.
- What If Results Are Off? Low creatinine might just mean diet tweaks; we’ll explain everything clearly.
Ready to safeguard your kidneys and live without worry?
Why Choose Blood Test UK For Your Kidney Test?
| Feature | DIY Kits | GP/NHS | Blood Test UK |
|---|---|---|---|
| Accuracy | ❌ Inconsistent samples | ✅ Lab-grade accuracy | ✅ Lab-grade accuracy (venous draw) |
| Convenience | ✅ Post it yourself | ❌ Long wait times | ✅ Nurse visits your home |
| Speed | ⚠️ Postal delays | ❌ Variable | ✅ Results within 2–3 days |
| Comfort | ❌ Self-prick | ⚠️ Clinic setting | ✅ Handled by professionals |
| Trust | ❌ Limited support | ✅ Professional | ✅ GP-shareable PDF report |
Testing For Kidney Health
If you’re worried about your kidney function or chronic kidney disease risk, a kidney blood test at home is particularly useful if you:
- Have high blood pressure or diabetes – the two most common causes of chronic kidney disease
- Have a family history of kidney disease or kidney failure
- Are overweight or obese, which increases your risk of both diabetes and kidney problems
- Smoke or have a history of heavy smoking
- Are over 60 years old, as kidney function naturally declines with age
- Have heart disease, <a href=”https://bloodtest.co.uk/cholesterol-blood-test/”>cardiovascular disease</a>, or have had a stroke
- Take medications regularly that can affect kidney function (such as NSAIDs like ibuprofen, certain blood pressure medications, or long-term painkillers)
- Have had acute kidney injury in the past
- Are already managing chronic kidney disease and want to monitor how well your treatment is working
- Have had abnormal kidney function results in the past and need a follow-up check
- Have made lifestyle changes (diet, weight loss, blood pressure control) and want to see if they’re helping
- Experience symptoms such as persistent fatigue, swelling in ankles or legs, changes in urination, or unexplained nausea
Kidney damage often develops silently with no obvious symptoms until function is significantly reduced, so a blood test is the only reliable way to assess your kidney health and discuss any concerns with a healthcare professional.
Can I Use These Results With My GP?
Yes. Your results are formatted as a professional PDF report that you can easily share with your NHS or private GP, kidney specialist, or other healthcare provider.
What Your Report Includes:
- eGFR result in mL/min/1.73m², as used in UK clinical practice for assessing kidney function
- Creatinine and urea levels showing how effectively your kidneys are clearing waste products
- Clear reference ranges indicating whether your results are normal or suggest reduced kidney function
- Laboratory accreditation details confirming the test meets professional standards
- Easy-to-understand format designed for both you and healthcare professionals
Important To Remember:
- Only a qualified healthcare professional who knows your full medical history can diagnose chronic kidney disease or determine its stage
- Your GP may want to repeat the test (as CKD diagnosis requires sustained low eGFR over three months) or order additional tests such as urine analysis before making a diagnosis
- Never start, stop, or change kidney medications or blood pressure treatments without medical advice
- If you have symptoms of severely reduced kidney function (extreme fatigue, significant swelling, confusion, nausea), seek urgent medical attention rather than waiting for test results
This test gives you the information you need to have an informed conversation with your doctor about your kidney health and next steps.
Nurse Appointments Fill Up Fast — Book Now to Secure Your Preferred Date.
How Often Should I Have A Kidney Blood Test?
The frequency depends on your individual circumstances:
- At-risk individuals: If you have high blood pressure, diabetes, or other risk factors above, checking your kidney function at least once a year can help detect early changes before symptoms appear
- General screening: Adults over 60 or those with a family history of kidney disease benefit from annual kidney function checks as part of routine health monitoring
- After lifestyle changes: If you’ve made significant changes to your diet, weight, blood pressure management or diabetes control, testing every 6–12 months can show if your efforts are protecting your kidneys
- People with chronic kidney disease: Those with diagnosed CKD typically need more frequent monitoring (every 3–12 months depending on CKD stage), as recommended by their GP or kidney specialist
- People on nephrotoxic medications: If you take medications that can affect kidney function long-term, your GP may recommend regular monitoring every 6–12 months
Note: These are general guidelines. Your GP or kidney specialist may recommend a different testing schedule based on your personal health profile, CKD stage, and treatment plan.
Evidence Behind Our Kidney Testing
Our at-home kidney blood test service is aligned with UK kidney health guidelines and modern laboratory standards, ensuring your results are suitable for long-term kidney function monitoring.
- eGFR as the kidney function standard: National guidance recommends eGFR (estimated Glomerular Filtration Rate) as the primary marker for assessing kidney function and detecting chronic kidney disease (CKD), with eGFR below 60 mL/min/1.73m² sustained over three months used to diagnose CKD stages 3–5.
Source: NICE chronic kidney disease guidance, Kidney Research UK CKD information
- Creatinine and urea for waste clearance: Serum creatinine and urea are key markers used alongside eGFR to assess how effectively your kidneys are removing waste products from your blood, with elevated levels suggesting reduced kidney function or other underlying issues.
Source: NHS kidney disease overview, NICE testing recommendations
- Early detection reduces complications: Research shows that detecting CKD early, particularly in people with high blood pressure, diabetes or a family history of kidney problems, allows lifestyle changes and medical interventions that can slow disease progression and reduce the risk of cardiovascular events.
- Venous sampling as the laboratory standard: Venous blood collection from the arm is the reference method used by hospital and accredited private laboratories for kidney function testing, providing sufficient sample volume and consistent quality for accurate eGFR, creatinine and urea analysis.
Source: Professional laboratory guidance
- Laboratory quality and accreditation: ISO 15189 is the international standard for medical laboratories and covers everything from sample handling to result reporting, so using UKAS ISO 15189‑accredited labs helps ensure your kidney function results are reliable and reproducible.
Source: UKAS medical laboratory accreditation, RCPath ISO 15189 overview
These guidelines and standards shape how we design our kidney tests, choose venous blood collection, and partner with UKAS ISO 15189‑accredited laboratories, so your results are produced to the same quality benchmarks used for decision‑making in NHS hospital care.
Nurse Appointments Fill Up Fast — Book Now to Secure Your Preferred Date.
Other Questions
- High blood pressure
- Smoking
- Excess alcohol consumption
- Frequent use of medication
- Family history of kidney disease
- Diabetes
- Older age
- Heart disease
This blood test is to check on:
-
Kidney health
For best results (if medically suitable) it is advisable to fast (water is allowed) 12 hours prior to the test.
Collection method: Venous blood
Results available: 1-2 days after the sample has reached the laboratory.
Urea
Urea is usually passed out through urine. It is a waste product from the breakdown of amino acids found in proteins.
Higher than normal levels may be indicative of a kidney problem, low levels may be indicative of dehydration.
Estimated glomerular filtration rate (eGFR)
This test will assess how well your kidneys are working.
Creatinine
Creatinine is usually passed out through urine. It is a breakdown of waste products made from the muscles.
A high level may be indicative of a kidney problem, however this does depend on muscle mass. Usually if a high muscle mass the creatinine may be higher. If levels are low it could be due to a low protein diet or reduced muscle mass.
Preparing For Your Kidney Blood Test
Kidney function testing does not require fasting, so you can prepare for your kidney blood test at home with minimal disruption to your normal routine.
- No fasting needed – you can eat and drink normally before your test. Kidney function markers like eGFR, creatinine and urea are not significantly affected by food intake on the day of testing.
- Take your usual medicines – unless your doctor or nurse tells you to do something different, continue taking your regular medications including any blood pressure tablets, diabetes treatments or supplements.
- Stay well hydrated – drinking water before your appointment can make the blood draw easier and more comfortable. Dehydration can sometimes cause a temporary rise in creatinine, so normal hydration gives the most accurate picture of your kidney function.
- Avoid strenuous exercise beforehand – intense physical activity in the 24 hours before your test can temporarily raise creatinine levels, so it’s best to avoid heavy workouts immediately before your appointment.
- Limit high-protein meals – while you don’t need to fast, extremely high-protein meals (such as large steak dinners) shortly before testing can temporarily elevate urea levels. Normal eating is fine, but avoid unusually protein-heavy meals in the hours before your appointment.
- Bring any previous results – if you have had kidney function tests before, it can help to compare changes over time and show your GP how your levels are trending.
- Wear comfortable clothing – choose something with sleeves that can be easily rolled up for the blood sample to be taken from your arm.
- Avoid heavy alcohol intake – try not to drink heavily in the 24 hours before your test, as alcohol can temporarily affect blood test results and hydration status.
If you are unsure about medication, have any health conditions that might affect testing, or have any questions, your nurse can answer these during your appointment.
How it Works
Read about Fingerprick VS Venous blood sample 
1. Order a Test
Order your test, and then Answer the Questions about why you’re taking that test.
Our nurse will contact you for dates, so they can take your blood sample at your home.
Our nurse will then send your sample to our laboratory.
2. Our laboratory team run the tests
Our skilled laboratory staff conduct your blood tests in a clean and secure environment, ensuring accuracy and reliability.
Each test follows strict protocols to maintain the highest quality standards.
3. Receive Your Results within 7 days
We will email you to inform you that your blood test results are ready.
The email will have a PDF report attached, sent directly to your inbox.
4. Monitor your levels over time
With regular ongoing tests and reports, you can track your results. The reports can be shared with your GP.
Check if you’re improving healthily or where changes could be made.
Kidney Blood Test FAQs
Do I Need To Fast Before A Kidney Blood Test?
No. Kidney function testing does not require fasting, so you can eat and drink normally before your appointment. This is one of the advantages of kidney function tests – you don't need to plan around meal times or go hungry before your blood draw.
What eGFR Level Is Considered Low?
In the UK, an eGFR below 60 mL/min/1.73m² sustained over three months is used to diagnose chronic kidney disease (CKD) stages 3–5. An eGFR of 60–89 with other signs of kidney damage indicates stage 2 CKD, while levels below 15 indicate kidney failure. Only your GP or kidney specialist can diagnose CKD based on your results and clinical history.
Can I Take This Test If I Already Have Kidney Disease?
Yes. If you're already managing chronic kidney disease, regular kidney function testing helps you and your healthcare team monitor how well your treatment is working and whether your condition is stable, improving or progressing. Most people with CKD check their kidney function every 3–12 months depending on the stage of their condition, though your GP or kidney specialist will advise on the right frequency for you.
How Long Will My Appointment Take?
The nurse visit typically takes 10–15 minutes. The blood sample itself only takes a few minutes to collect, with a little extra time for paperwork and answering any questions you may have.
When Will I Get My Results?
Results are typically available within 1–2 days of your blood sample reaching the laboratory, making our kidney blood test at home service both convenient and quick. You'll receive your results by email as a PDF report that you can save, print, or share with your GP.
What Should I Do If My Kidney Function Results Are Abnormal?
If your eGFR, creatinine or urea levels are outside the normal range, book an appointment with your GP to discuss your results. Your GP may want to repeat the test (as CKD diagnosis requires sustained low eGFR over three months), order additional tests such as urine analysis, or refer you to a kidney specialist. They can also advise on lifestyle changes, blood pressure management, or treatment options. Early detection gives you the best opportunity to protect your kidney function and prevent complications.
Can I Use These Results With My NHS GP?
Yes. Your results are provided as a professional laboratory report in a format suitable for sharing with NHS or private GPs, kidney specialists, or other healthcare providers. The report includes all necessary technical information and reference ranges used in UK clinical practice.
Is Venous Blood Testing More Accurate Than Finger-Prick Tests?
Yes. Venous blood samples taken from your arm by a nurse are the gold standard for laboratory testing. They provide more blood volume for analysis, reduce the risk of sample contamination or haemolysis (red blood cell breakdown), and deliver more consistent and reliable results compared to finger-prick capillary samples.
What If I Have High Blood Pressure Or Diabetes?
High blood pressure and diabetes are two of the most common causes of chronic kidney disease, so regular kidney function testing is particularly important if you have either condition. Your kidney test results can help your GP assess whether these conditions are affecting your kidneys and whether any adjustments to your treatment plan are needed. Consider also checking your cholesterol levels and liver function, as these often go hand-in-hand with kidney health monitoring.
Can Dehydration Affect My Kidney Test Results?
Yes. Dehydration can cause a temporary rise in creatinine and urea levels, which may make your kidney function appear worse than it actually is. This is why we recommend drinking water normally before your appointment – it helps ensure your results reflect your true kidney function rather than temporary dehydration.
