Kidney failure occurs when your kidneys lose the ability to filter waste from your blood sufficiently. It may not cause symptoms in the early stages.

Your kidneys filter your blood and remove toxins from your body. These toxins go to your bladder and are eliminated when you urinate. When this doesn’t work properly, you can get kidney failure.

If your kidneys aren’t able to function properly, toxins can overwhelm your body. This can lead to kidney failure, which can be life threatening if left untreated.

Keep reading as we break down everything you need to know about kidney failure, including symptoms, stages, treatment, and the typical outlook.

Acute kidney failure occurs when your kidneys suddenly stop working properly while chronic kidney failure occurs over time. Doctors typically divide kidney failure into five types.

The types of kidney failure include:

  • Acute prerenal kidney failure: Insufficient blood flow to the kidneys can cause acute prerenal kidney failure. Doctors can usually cure this type once they determine the cause of the decreased blood flow.
  • Acute intrinsic kidney failure: Acute intrinsic kidney failure can result from direct trauma to the kidneys, such as physical impact or an accident, toxin overload, and ischemia, which is a lack of oxygen to the kidneys.
  • Chronic prerenal kidney failure: When there isn’t enough blood flowing to your kidneys for an extended period of time, the kidneys can shrink and lose the ability to function.
  • Chronic intrinsic kidney failure: This happens when there’s long-term damage to the kidneys due to intrinsic kidney disease. Intrinsic kidney disease develops from direct trauma to the kidneys, such as severe bleeding or a lack of oxygen.
  • Chronic post-renal kidney failure: A long-term blockage of the urinary tract prevents urination. This causes pressure and eventual kidney damage.
  • Acute post-renal kidney failure: This type of kidney failure can occur due to stones or another blockage in the urinary tract.

Early-stage kidney failure often doesn’t cause noticeable symptoms. According to the Centers for Disease Control and Prevention (CDC), about 90% of people with chronic kidney disease don’t know they have it.

As kidney disease progresses, symptoms may include:

Early signs of kidney failure

Symptoms of early-stage kidney disease may be subtle and hard to identify. They may include:

Kidney failure urine color

The color of your urine doesn’t tell you much about the state of your kidney function until damage to the kidneys has progressed.

Still, urine color changes may be an early indicator of some issues.

Urine colorIndication
clear or pale yellowwell-hydrated
dark yellow or amberdehydrated
orangedehydration or bile in the bloodstream
pink or redblood in the urine or having eaten certain foods, like beets
foamycontains a lot of protein; potentially an indicator of kidney disease

Kidney failure can result from various causes. According to the National Kidney Foundation, the two most common include high blood pressure and diabetes.

People who are most at risk usually have one or more of the following:

Loss of blood flow to the kidneys

A sudden loss of blood flow to your kidneys can prompt kidney failure. Some causes include:

High blood pressure and anti-inflammatory medications can also limit blood flow.

Urine elimination problems

When your body can’t eliminate urine, toxins build up and overload the kidneys. Some cancers can block the urine passageways, such as:

Other conditions can interfere with urination and possibly lead to kidney failure, including:

Other causes

Other factors that may lead to kidney failure include:

People of all ages develop kidney failure, but the risk increases with age. According to the CDC, 14% of U.S. adults have chronic kidney failure.

You may have a higher risk if you have:

  • diabetes
  • high blood pressure
  • heart disease
  • a family history of kidney failure

The longer you’ve had these conditions, the greater your risk of chronic kidney failure.

Doctors use several tests to diagnose kidney failure. Common tests include:

  • Urinalysis: A urine sample can show how much protein or sugar is in your urine. A urinary sediment examination looks for red and white blood cells, high levels of bacteria, and high numbers of cellular casts.
  • Urine volume measurements: Measuring urine output can help diagnose kidney failure. Low output may suggest that kidney disease is due to a urinary blockage.
  • Blood samples: Blood tests can measure substances filtered by your kidneys, such as blood urea nitrogen and creatinine. A rapid rise in these levels may indicate acute kidney failure.
  • Imaging: Tests like ultrasounds, MRIs, and CT scans provide images of your kidneys and urinary tract to identify issues.
  • Kidney tissue sample: Doctors use a kidney biopsy to collect and examine tissue samples.

Kidney disease is classified into five stages. These range from very mild (stage 1) to complete kidney failure (stage 5). Symptoms and complications increase as the stages progress.

Stage 1

You may experience no symptoms and have no visible complications. But some kidney damage is present.

Stage 2

Stage 2 kidney disease is still considered mild, but detectable issues like protein in the urine or physical damage to the kidneys may be more obvious.

It’s also a good idea to talk with a doctor about risk factors that could make the disease progress more rapidly, such as:

Stage 3

At this stage, your kidneys aren’t working as well as they should.

Stage 3 kidney disease is sometimes divided into stages 3a and 3b. A blood test that measures the amount of waste products in your body helps doctors differentiate between the two.

Symptoms may become more apparent. Swelling in hands and feet, back pain, and changes to urination frequency are likely.

A doctor may consider medications to treat underlying conditions that could speed kidney failure.

Stage 4

Stage 4 kidney disease is considered moderate to severe. The kidneys aren’t working well, but you’re not in complete kidney failure yet. Symptoms can include complications like:

A doctor will likely develop a treatment plan to slow kidney damage.

Stage 5

In stage 5, your kidneys are nearing or in complete failure. Symptoms of the loss of kidney function will be evident, such as vomiting and nausea, trouble breathing, and itchy skin.

You’ll need regular dialysis or a kidney transplant.

The National Institute of Diabetes and Digestive and Kidney Diseases estimates that approximately 1 in 500 Americans has stage 5 kidney failure.

The type of treatment you need depends on the cause and stage of your kidney failure.


Dialysis filters and purifies the blood using a machine to performs the function of the kidneys. Depending on the type of dialysis, you may be connected to a large machine or a portable catheter bag.

Along with dialysis, you may need to follow a low potassium, low salt diet.

Dialysis doesn’t cure kidney failure, but going to regularly scheduled treatments can extend your life.

Kidney transplant

A transplanted kidney can work fully, so you no longer need dialysis.

There’s usually a long wait to receive a donor kidney that’s compatible with your body. If you have a living donor, the process may go more quickly.

Transplant surgery might not be the right treatment option for everyone. It is not always successful.

You must take immunosuppressant drugs after the surgery to prevent your body from rejecting the new kidney. These drugs have their own side effects, some of which can be serious.

You can talk with a doctor about whether you’re a good candidate for a kidney transplant.

Lifestyle modifications

Minimizing your intake of alcohol and making dietary changes may help prevent kidney failure from progressing.

At the early stages and beyond, it’s possible to manage and slow progression with lifestyle factors such as:

Dietary changes

The guidelines for what you eat will often depend on the stage of kidney disease you have and your overall health. Some recommendations might include:

  • Limiting sodium and potassium: Aim to eat less than 2,000 milligrams per day of both sodium (salt) and potassium.
  • Limiting phosphorus: Try to stay below 1,000 milligrams of phosphorus.
  • Following protein guidelines: In early and moderate kidney disease, you might want to cut back on protein consumption. But you may eat more protein in end-stage kidney failure, depending on your doctor’s recommendations.

Beyond these general guidelines, a doctor may also ask you to avoid certain foods.

Lowering alcohol intake

If you have kidney failure and drink alcohol, your kidneys must work harder than they already do. Alcohol doesn’t metabolize out of your system, so if you have complete kidney failure, you’ll feel its effects until you receive dialysis to filter it from your blood.

Beer, ale, and wine also contain large amounts of phosphorous. Severe heart issues and death are possible if your kidneys cannot filter it out.

If you have kidney failure or late-stage kidney disease, a doctor may recommend you limit alcohol. Eliminating alcohol from your diet, if possible, may be best.

Diabetes is the most common cause of kidney failure. About one-third of adults with diabetes have kidney disease.

Without management, high blood sugar can damage your kidneys. The damage can worsen over time.

Diabetic nephropathy, or kidney damage caused by type 1 or type 2 diabetes, can’t be reversed. Steps to prevent or limit kidney damage can include:

  • managing your blood sugar
  • managing blood pressure
  • taking medications as prescribed

If you have diabetes, a doctor will likely perform regular screenings to monitor for kidney failure. Your risk for diabetic nephropathy increases the longer you live with diabetes.

Kidney failure can lead to various complications. These can include:

Many people with kidney failure develop secondary complications. These can include:

It’s not possible to know precisely how long a person with kidney failure will live, as it can depend on many factors.

These include:

  • the underlying cause
  • how well that underlying cause is managed
  • any complicating factors, like high blood pressure or diabetes
  • stage of kidney disease at diagnosis
  • age

The National Kidney Foundation says that a person on dialysis can expect to live for an average of 5 to 10 years as long as they follow their treatment. Some people live for more than 20 or 30 years.

Once you reach end-stage kidney failure, you will need dialysis or a kidney transplant to live. Missing even one dialysis treatment can decrease your life expectancy.

Proper treatment and healthy lifestyle changes may improve your outlook, such as avoiding certain foods.

You can take steps to lower the risk of kidney failure.

Follow directions when taking over-the-counter medications. Taking doses that are too high, even of common drugs like aspirin, can create high toxin levels quickly. This can overload your kidneys.

Many kidney or urinary tract conditions lead to kidney failure without prompt treatment.

You can help lower your risk of kidney failure by:

  • eating a balanced diet
  • maintaining a moderate weight
  • taking prescribed and over-the-counter medications as directed and not taking more medication than is safe
  • keeping conditions, such as diabetes and high blood pressure, well managed and following a doctor’s advice

Kidney failure can develop suddenly or from long-term damage. Possible causes of kidney failure can include diabetes, high blood pressure, and kidney trauma.

Kidney disease is classified into five stages, ranging from mild to complete kidney failure. Symptoms and complications increase as the stages progress.

If you have kidney failure, you can work with a doctor to determine the best treatment options.