Dialysis is a treatment that takes over the job of your kidneys if they fail]]>. The kidneys have many functions that help your body stay healthy. They help clear toxins out of your blood and help your body balance salt levels. Most patients begin dialysis when their kidneys have lost 85%-90% of their ability. You may be on dialysis for a short time, or you may need it for the rest of you life (or until you receive a kidney transplant), depending on the reason for your kidney failure.

If you have kidneys that are not working and the damage is not reversible, you have end stage enal disease (ESRD). ESRD is caused by conditions such as diabetes, ]]>kidney cancer]]>, drug use, ]]>high blood pressure]]>, or other kidney problems. Dialysis is not a cure for ESRD, but it does help you feel better and live longer.

There are two types of dialysis: hemodialysis and peritoneal dialysis. This fact sheet will focus on hemodialysis.


Reasons for Procedure

The main functions of hemodialysis are to:

  • Remove waste and excess fluid from your blood
  • Control blood pressure
  • Keep a safe level of salts in the body, such as potassium, sodium, and chloride

It may also be done to remove toxins from the bloodstream quickly. This can be used in cases of poisoning or drug overdose.

Possible Complications

Complications are rare, but no procedure is completely free of risk. If you are planning to have hemodialysis, your doctor will review a list of possible complications. These may include:

  • Lowering your red blood count and causing anemia]]>
  • Drop in blood pressure during hemodialysis
  • Muscle cramps
  • Nausea, vomiting
  • Headaches
  • Infection
  • Feeling hot, sweaty, weak, and/or dizzy
  • Inflammation of the heart sac (]]>pericarditis]]>)
  • Neurologic problems
  • Disruption of calcium and phosphorus balance, resulting in weakened bones

Also, having heart problems is a factor that may increase the risk of complications from hemodialysis.


What to Expect

Prior to Procedure

Usually, before your first hemodialysis, you will have some sort of tubing attached to a large vein to make blood flow from your body to the machine and back more easily. If you will be on hemodialysis for a long time, you may have had surgery to create a shunt or a fistula, which makes access to a large vein easier. Fistulas may need as long as 2–3 months to fully heal before they can be used. They are not used if the treatment is temporary. They are typically created many months before hemodialysis begins.

Other things that will happen before your hemodialysis are:

  • Weight, blood pressure, and temperature are taken.
  • Topical anesthetic (a pain-numbing medicine) is usually applied to the area of needle insertion, if needle insertion is needed.
  • Heparin]]> is given to prevent blood clotting.


You will be given a topical anesthetic.

Description of the Procedure

Hemodialysis is done at a dialysis center or hospital. It may be done at home with assistance.

During the procedure, blood is filtered through an artificial kidney machine, called a dialyzer. The blood travels from your body to the machine through tubes inserted into a large vein in your body. Once the blood is filtered in the machine, it travels back into your body through another tube.


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How Long Will It Take?

Hemodialysis is usually done three times a week. Each treatment can last anywhere from 2-4 hours. The specific time needed depends on a few factors:

  • How much kidney function remains
  • How much fluid weight gain has occurred since the last treatment
  • Amount of waste in the body
  • Body size
  • Level of salts in your body, such as sodium, potassium, and chloride

Will It Hurt?

In general, hemodialysis does not cause pain. You will not feel the blood exchange. There may be some temporary discomfort with the insertion of the needle or tube.

Post-procedure Care

At the Care Center

Your blood pressure will be monitored. Once the procedure is complete and blood pressure is stable, you are free to continue daily activities.

At Home

Be sure to follow your doctor’s instructions. There are some special considerations:

Dietary Guidelines

Certain dietary guidelines should be followed. This will help to maintain overall health and optimize treatment effects. Talk to your doctor about your specific dietary needs.


Your doctor may give you various medicines. These include, but are not limited to:

  • Blood pressure medicines
  • Calcium supplements or multivitamins
  • Phosphorus binders—to lower phosphorus levels in the blood
  • Diuretics—to remove excess fluid
  • Stool softeners or laxatives—to prevent or treat constipation, which can be caused by decreased fluid intake
  • Iron supplements—to increase iron intake, which is important for production of red blood cells
  • Medicines to stimulate the body to produce more red blood cells

Call Your Doctor

After arriving home, contact your doctor if any of the following occurs:

  • Signs of infection, including fever and chills
  • Redness, swelling, warmth, increasing pain, excessive bleeding, or discharge at the catheter or tube insertion site
  • Nausea or vomiting
  • Abdominal pain
  • Dizziness or weakness
In case of an emergency, CALL 911.