What are the first signs of kidney problems?

Usually there are none: early kidney disease rarely causes symptoms, and it's most often found on a routine blood or urine test. When early signs do appear, they can include frothy pee, puffy eyes in the morning, swollen ankles or peeing more at night. Because these are easy to miss, people at risk should be tested regularly.

What are the symptoms of kidney damage?

As kidney damage progresses, common symptoms are swollen ankles, feet or hands, tiredness, shortness of breath, itchy skin, muscle cramps, poor appetite and weight loss, feeling sick, trouble sleeping, peeing more at night, and blood or froth in the pee. These have many other causes too, so a blood test (eGFR) and a urine test (ACR) are needed to know.

What are the signs of kidney failure?

Kidney failure is the last stage of chronic kidney disease, when the eGFR is below 15. Signs include marked tiredness, swelling, breathlessness, itching, poor appetite, nausea and vomiting, muscle cramps, trouble sleeping and poor concentration. Sudden kidney failure (acute kidney injury) can also cause peeing much less than usual, and needs a doctor the same day.

Where is kidney pain felt, and is back pain a sign of kidney disease?

Kidney pain is felt in the side or back, just below the ribs. But chronic kidney disease is usually painless. Pain there with fever and shivering suggests a kidney infection, and severe cramping pain spreading to the groin suggests a kidney stone; both need a doctor. Most lower back pain comes from muscles and joints, not the kidneys.

What does urine look like when the kidneys are damaged?

Foamy or frothy pee that doesn't settle can mean protein is leaking. Pink, red or cola-coloured pee can mean blood, which always needs a doctor. Peeing much less than usual can be a sign of acute kidney injury. Dark yellow pee usually just means you need to drink more, and some foods and medicines change the colour too.

Can kidney disease cause swelling?

Yes. When the kidneys can't remove enough salt and water, fluid builds up, often in the ankles, feet and hands, and as puffiness around the eyes when protein is leaking. Swelling also has many other causes, including heart, liver and vein problems and some medicines, so see a doctor for a blood and urine test.

Which tests check kidney function?

The two main tests are a blood test for creatinine, which the lab turns into an eGFR, and a urine test for albumin, the albumin-to-creatinine ratio (ACR). Together they find most kidney disease early. A doctor may add a urine dipstick, an ultrasound scan of the kidneys, and blood tests such as potassium and a full blood count.

What eGFR means kidney disease?

An eGFR below 60 for three months or more means chronic kidney disease. An eGFR of 60 or more can still be kidney disease if there are other signs of damage, such as protein in the urine. Below 15 means kidney failure. One low result isn't a diagnosis: doctors repeat the test. Our creatinine guide explains the stages.

Who should get their kidneys tested?

People with diabetes (every year), high blood pressure, heart disease, a family history of kidney failure, a past acute kidney injury, or long-term use of medicines that can affect the kidneys. Being over 60, or of south Asian or black origin, also raises the risk. Ask your doctor how often you need a blood and urine test.

Can painkillers damage the kidneys?

Regular, long-term use of anti-inflammatory painkillers (NSAIDs such as ibuprofen or diclofenac) can harm the kidneys, especially if you're older, dehydrated, or already have kidney, heart or liver problems. If you need pain relief often, ask a doctor or pharmacist which option is safest for you. Don't stop a prescribed medicine without advice.

Can kidney damage be reversed?

Acute kidney injury often recovers fully within weeks when the cause is treated quickly. Chronic kidney disease can't usually be reversed, but it can often be slowed or stopped from getting worse by controlling blood pressure and blood sugar, taking kidney-protecting medicines your doctor prescribes, and avoiding harmful medicines. The earlier it's found, the more there is to protect.

Are kidney disease symptoms different in women?

Mostly they're the same. Women get urine infections more often, and an untreated infection can spread to the kidneys. In advanced kidney disease, periods can become irregular or stop. In pregnancy, protein in the urine with high blood pressure can be a sign of pre-eclampsia, which needs urgent care: your midwife or doctor checks for both.

Kidney disease symptoms: the signs of kidney damage, and the tests that find it

Kidney disease is usually silent until it's advanced. Here's what the signs look like when they do appear, who should get checked anyway, and the two simple tests that tell.

Updated November 14, 2026 · Sources

Quick answer

What are the symptoms of kidney disease?

Early kidney disease usually causes no symptoms, which is why blood and urine tests matter. When symptoms appear, often at a later stage, they include swollen ankles, feet or hands, tiredness, shortness of breath, itchy skin, muscle cramps, poor appetite, feeling sick, peeing more at night, and blood or froth in the pee.

Ask about my symptoms Explain my report

Health information, not medical advice. Your doctor knows your full picture; ask them about your result.

Side by side

Chronic kidney disease vs acute kidney injury: how the signs differ

Kidney damage comes in two forms. Chronic kidney disease (CKD) builds over months or years; acute kidney injury (AKI) happens over hours or days and needs a doctor quickly.

What you notice	Chronic kidney disease	Acute kidney injury
How fast	Slowly, over months or years	Suddenly, over hours or days
Early on	Usually no symptoms at all	Often no symptoms if mild
Peeing	Peeing more often, especially at night	Peeing much less than usual
What the pee looks like	Frothy or foamy pee; sometimes blood in it	Can be dark; depends on the cause
Swelling	Ankles, feet, hands; puffy eyes	Feet and legs
How you feel	Tired, itchy, poor appetite, cramps, poor sleep	Very thirsty, sick or vomiting, dizzy, confused or sleepy
Breathing	Breathless in later stages	Breathless, especially when lying down
Common causes	Diabetes and high blood pressure	Infection, dehydration, a blockage, some medicines
Outlook	Lifelong, but treatment can slow it	Many people recover within weeks with treatment

Swollen ankles, breathlessness and tiredness also have many other causes, including heart, liver and vein problems. Blood and urine tests are what tell kidney damage apart.

What do the kidneys do?

You have two kidneys, each about the size of a fist, below your ribs on either side of your spine. Every minute they filter your blood, removing waste and extra water as urine. They also keep your salts and minerals in balance, help control blood pressure, help make red blood cells and keep bones strong.

Chronic kidney disease (CKD) means the kidneys are damaged and filter less well than they should, for three months or longer. It's common, especially with age, and it's more common in people of south Asian or black origin.

The kidneys have a lot of spare capacity, so they can lose much of their function before you feel anything. The National Kidney Foundation estimates that only about 1 in 10 people with CKD know they have it. That's why tests, not symptoms, are how kidney disease is usually found.

What are the early and later signs of kidney damage?

Early on: usually nothing at all. The first clue is often a routine blood or urine test done for another reason. Some people notice frothy pee, puffy eyes or peeing more at night, which can be early signs of protein leaking or of the kidneys concentrating urine less well.

Later, as function falls:

Fluid signs: swollen ankles, feet or hands, puffy eyes, breathlessness
Urine signs: peeing more, especially at night, blood in the pee, foamy pee
Waste build-up signs: tiredness, itchy or dry skin, poor appetite and weight loss, feeling sick, muscle cramps, trouble sleeping, poor concentration, headaches
In men: erectile problems. In women: periods can become irregular or stop in advanced disease.

When kidneys fail (stage 5): these symptoms become stronger, and dialysis or a transplant may be needed. NHS figures say this happens in only around 2 in 100 people with CKD; most people manage it with medicines and check-ups.

Acute kidney injury (AKI) is different: it comes on over hours or days, often during another illness. Signs include peeing much less than usual, feeling very thirsty, nausea or vomiting, swollen legs, confusion or drowsiness, and breathlessness when lying down. AKI needs a doctor the same day.

Does kidney disease hurt?

Usually not. Chronic kidney disease is almost always painless, which is one reason it goes unnoticed.

Pain that comes from the kidneys is felt in the side or back, just below the ribs, and usually has a different cause:

Kidney infection: pain in the side or back with fever, shivering, feeling sick, and often burning when peeing. It needs a doctor the same day.
Kidney stones: severe, cramping pain that comes in waves, from the back or side towards the groin, sometimes with blood in the pee.

Most lower back pain comes from muscles and joints, not the kidneys. Back pain alone, with no fever and no change in your pee, is rarely a kidney problem.

What causes kidney damage?

Diabetes: high blood sugar damages the kidneys' tiny filters. It's one of the two most common causes.
High blood pressure: strains the small blood vessels in the kidneys. It's the other most common cause, and kidney disease can raise blood pressure further.
Heart disease and high cholesterol, which affect the blood vessels that supply the kidneys.
Kidney inflammation (glomerulonephritis), repeated kidney infections and inherited conditions such as polycystic kidney disease.
Blockages to the flow of urine, such as kidney stones that keep coming back or an enlarged prostate.
Long-term use of some medicines, such as regular anti-inflammatory painkillers (NSAIDs like ibuprofen or diclofenac) and lithium. Don't stop a prescribed medicine because of this: ask your doctor whether you need kidney tests.
A past acute kidney injury, which can leave lasting damage.

Who should get their kidneys checked?

Because early kidney disease is silent, people at higher risk are advised to have regular tests even when they feel well:

Diabetes: a kidney check every year
High blood pressure or heart disease
A family history of kidney failure or inherited kidney disease
A past acute kidney injury, kidney stones that keep coming back, an enlarged prostate or lupus
Long-term medicines that can affect the kidneys, such as lithium or regular NSAID painkillers
Age over 60, and people of south Asian or black origin, who have a higher risk
Protein or blood found in the urine before, with no known cause

Ask your doctor how often you should be tested.

Which tests check your kidneys?

Two simple tests find most kidney disease, usually long before symptoms:

A blood test for creatinine, a waste product your kidneys clear. The lab turns it into an eGFR (estimated glomerular filtration rate), which shows how much blood your kidneys filter each minute. An eGFR below 60 for three months or more means CKD, and below 15 means kidney failure. Our creatinine guide explains the numbers and stages, with a calculator.
A urine test for albumin, a protein that healthy kidneys keep in the blood. The albumin-to-creatinine ratio (ACR) shows how much is leaking.

ACR category	mg/mmol	mg/g	What it means
A1	Below 3	Below 30	Normal to mildly raised
A2	3 to 30	30 to 300	Moderately raised
A3	Above 30	Above 300	Severely raised

Reports use either unit, so check which one yours prints. A raised result is usually repeated to confirm it, because exercise, an infection or a period can raise it for a while.

Doctors may also do a urine dipstick for blood and protein, an ultrasound scan to look at the kidneys, and other blood tests such as potassium and a full blood count (CBC), because kidney disease can cause anaemia.

How is it treated, and how can you protect your kidneys?

There's no cure for chronic kidney disease, but treatment can slow it down and protect the heart, and the earlier it starts the better.

Blood pressure control is the most important step. Doctors often use medicines that also protect the kidneys; your doctor decides which and how much.
Blood sugar control if you have diabetes. Some diabetes medicines also help the kidneys keep working for longer.
Medicines to lower cholesterol and protect the heart, because CKD raises the risk of heart attack and stroke.
Check before any new medicine, painkiller, supplement or herbal remedy, including traditional remedies: some can harm the kidneys, and many medicines need a different dose when the kidneys filter less. Tell every doctor and pharmacist your eGFR.
Don't smoke, stay active, aim for a healthy weight and eat less salt. A dietitian can advise on protein, potassium and phosphate if your kidney function is low.
Drink enough that your pee is pale, unless your doctor has told you to limit fluids.
Keep your check-ups. Repeat blood and urine tests show whether treatment is working.

If the kidneys fail, dialysis or a kidney transplant replaces their work. Your kidney team will talk about this long before you need it.

When to see a doctor

Book an appointment

Blood in your pee, even once and without pain: see your GP or family doctor within a few days.
New swelling of the ankles, feet or hands, foamy pee or peeing at night that lasts more than a week: see your GP or general physician within one to two weeks for a blood and urine test.
Diabetes, high blood pressure, heart disease or a family history of kidney failure, and no kidney test in the past year: ask for one at your next appointment, within the next few weeks.
Known kidney disease with new swelling, more breathlessness or rising blood pressure readings: see your doctor or nephrologist (kidney specialist) within a few days.
Taking anti-inflammatory painkillers regularly, lithium, or herbal remedies, and noticing any of these symptoms: talk to your doctor or pharmacist this week.

Get emergency help now (call your local emergency number) if someone has:

very little or no pee for a day, especially with vomiting, diarrhoea or a serious infection
breathlessness at rest, or can't lie flat because of breathlessness
chest pain, a very slow, fast or irregular heartbeat, or sudden muscle weakness
sudden confusion, extreme drowsiness or a seizure
a high fever with severe pain in the side or back, shivering or vomiting

Most kidney disease builds slowly and can be managed for years. These signs are the exceptions that can't wait.

Swollen ankles, foamy pee, a worrying report? Talk it through.

Saluvo listens to how you feel, in your own words and language, asks the right follow-up questions, and tells you which doctor to see and how soon. Already have a kidney function test? It explains your creatinine, eGFR and every other value.

Ask about my symptoms

Free to start. Describe what you feel in your own words and language.

Questions people ask

Usually there are none: early kidney disease rarely causes symptoms, and it's most often found on a routine blood or urine test. When early signs do appear, they can include frothy pee, puffy eyes in the morning, swollen ankles or peeing more at night. Because these are easy to miss, people at risk should be tested regularly.
As kidney damage progresses, common symptoms are swollen ankles, feet or hands, tiredness, shortness of breath, itchy skin, muscle cramps, poor appetite and weight loss, feeling sick, trouble sleeping, peeing more at night, and blood or froth in the pee. These have many other causes too, so a blood test (eGFR) and a urine test (ACR) are needed to know.
Yes, and most people do. The kidneys have a lot of spare capacity, so they can lose much of their function before you feel unwell. The National Kidney Foundation estimates that only about 1 in 10 people with chronic kidney disease know they have it. That's why yearly tests matter if you have diabetes or high blood pressure.
Kidney failure is the last stage of chronic kidney disease, when the eGFR is below 15. Signs include marked tiredness, swelling, breathlessness, itching, poor appetite, nausea and vomiting, muscle cramps, trouble sleeping and poor concentration. Sudden kidney failure (acute kidney injury) can also cause peeing much less than usual, and needs a doctor the same day.
Kidney pain is felt in the side or back, just below the ribs. But chronic kidney disease is usually painless. Pain there with fever and shivering suggests a kidney infection, and severe cramping pain spreading to the groin suggests a kidney stone; both need a doctor. Most lower back pain comes from muscles and joints, not the kidneys.
Foamy or frothy pee that doesn't settle can mean protein is leaking. Pink, red or cola-coloured pee can mean blood, which always needs a doctor. Peeing much less than usual can be a sign of acute kidney injury. Dark yellow pee usually just means you need to drink more, and some foods and medicines change the colour too.
Yes. When the kidneys can't remove enough salt and water, fluid builds up, often in the ankles, feet and hands, and as puffiness around the eyes when protein is leaking. Swelling also has many other causes, including heart, liver and vein problems and some medicines, so see a doctor for a blood and urine test.
The two main tests are a blood test for creatinine, which the lab turns into an eGFR, and a urine test for albumin, the albumin-to-creatinine ratio (ACR). Together they find most kidney disease early. A doctor may add a urine dipstick, an ultrasound scan of the kidneys, and blood tests such as potassium and a full blood count.
An eGFR below 60 for three months or more means chronic kidney disease. An eGFR of 60 or more can still be kidney disease if there are other signs of damage, such as protein in the urine. Below 15 means kidney failure. One low result isn't a diagnosis: doctors repeat the test. Our creatinine guide explains the stages.
People with diabetes (every year), high blood pressure, heart disease, a family history of kidney failure, a past acute kidney injury, or long-term use of medicines that can affect the kidneys. Being over 60, or of south Asian or black origin, also raises the risk. Ask your doctor how often you need a blood and urine test.
Regular, long-term use of anti-inflammatory painkillers (NSAIDs such as ibuprofen or diclofenac) can harm the kidneys, especially if you're older, dehydrated, or already have kidney, heart or liver problems. If you need pain relief often, ask a doctor or pharmacist which option is safest for you. Don't stop a prescribed medicine without advice.
Acute kidney injury often recovers fully within weeks when the cause is treated quickly. Chronic kidney disease can't usually be reversed, but it can often be slowed or stopped from getting worse by controlling blood pressure and blood sugar, taking kidney-protecting medicines your doctor prescribes, and avoiding harmful medicines. The earlier it's found, the more there is to protect.
Mostly they're the same. Women get urine infections more often, and an untreated infection can spread to the kidneys. In advanced kidney disease, periods can become irregular or stop. In pregnancy, protein in the urine with high blood pressure can be a sign of pre-eclampsia, which needs urgent care: your midwife or doctor checks for both.

Tests that help

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Sources

Updated November 14, 2026. Health information, not medical advice. Your doctor knows your full picture; ask them about your result.