Hemodialysis is a therapy that filters waste, removes extra fluid and balances electrolytes (sodium, potassium, bicarbonate, chloride, calcium, magnesium and phosphate).

How is hemodialysis done?

During dialysis, your blood is pumped through a filter called a dialyzer. The dialyzer has two compartments separated by a membrane. Blood flows through one side. A solution called dialysate circulates on the other side of the membrane. As blood flows through, waste products and excess fluid filter through the membrane and transfer to the dialysate side. The waste-filled dialysate is removed and replaced by fresh solution throughout your dialysis treatment. Your doctor will prescribe how long your treatment sessions will last.

When you arrive, you will have your weight checked. This is very important to determine the settings on your dialysis machine for removal of excess fluid in your blood. Drinks and ice intake will be strictly monitored while on dialysis. Once you enter the dialysis area you will not be allowed to drink any fluid (including ice) until your treatment is started and your technician has given you the okay. You will be weighed again after your dialysis is completed.

Patients typically have two concerns with dialysis – how long will it take and how will the blood be taken out of my body and returned?

How long will dialysis take?

You need to schedule time for your dialysis. It takes several hours to get all of your blood filtered during each treatment session. Typically, in-center hemodialysis is done three times a week for three to four hours per treatment. The actual time will depend upon your body size, overall medical condition and your laboratory blood test results.

Appointments are usually set up in shifts at each dialysis center. You will be scheduled the same time each day for your treatments. The center staff will do their best to accommodate work schedules. Typical treatment schedules have patients coming to the dialysis centers either Monday, Wednesday, Friday or Tuesday, Thursday, Saturday.

Diet & nutrition

You will be assigned to a dietitian who will work directly with you and your family to plan meals and guide you on the right food choices. Your dietitian will meet with you at least once a month to go over results from laboratory blood tests and adjust your diet accordingly.

Learn more about diet and your kidneys »


Thousands of people maintain active lives while undergoing regular dialysis. With careful scheduling around your dialysis treatments, you may be able to continue to work and keep up with leisure activities, even travel.

If you are not able to continue working due to disability once you start dialysis, you can apply for Social Security Disability Insurance by calling 1-800-772-1213. You can also apply at the local social security office or through the human resources department at your place of employment.

Learn more about lifestyle »


If you need transportation to dialysis and meet eligibility requirements, state Medicaid may cover costs to get you to and from your dialysis center. It may take a few weeks to get the paperwork turned in and approved by Medicaid, however, so you should plan on finding your own transportation for the first 10 dialysis treatments. Social workers at the dialysis unit will assist you with transportation planning. You may need help from friends and family to get you to and from your treatments.

Financial concerns

Everyone who needs hemodialysis will receive the appropriate medical treatment. Washington University charges for doctor’s services. Barnes-Jewish Hospital charges for tests and procedures. Staff from both billing offices will determine your insurance coverage for dialysis. If your insurance plans are out of network for either or both services, causing a very high co-pay, we will help you find the best dialysis unit that your insurance will cover.

You may already have or be eligible for Medicare. Medicare will combine with your health insurance to cover dialysis costs. If you have group health insurance from your job, Medicare will be a secondary insurance for the first 30 months of dialysis.

Medicare usually becomes the primary payer after 30 months, no matter what your age is. If you do not have Medicare at this time, Medicare will start to pay for your hemodialysis treatment at a center on the first day of your third full month of hemodialysis. The social workers and business office will help you apply for Medicare. State Medicaid also pays for dialysis. Medicare Part D will help pay for medications.

Emotional concerns

It may be difficult to adjust to dialysis therapy. You and your family may be anxious and overwhelmed with all you have learned, the decisions and plans. This is normal and expected. It’s important to note though, most people feel their lives get back to normal in a short period of time after starting dialysis and are able to adjust to treatments and medications. Talk to your family, health care team or spiritual advisor and social worker for help with coping with the stress associated with your initial adjustment.

Dialysis on the go (travel)

If you travel for business or pleasure, you can still learn to dialyze on the go. The key is learning to plan in advance. First, check with your physician to see if it is okay to travel. Then, tell the dialysis team your travel dates so we can help coordinate referrals and insurance coverage. Because planning all of the logistics takes time, you should begin your advance planning four to six weeks before your scheduled trip.

For in-center dialysis, you will need to find a dialysis unit close to your destination. There are even some cruise lines that offer dialysis while on board. A list of dialysis units in the United States can be found on the internet. Examples of good websites include:

If you don’t have internet access, ask your renal team to look up center phone numbers for you.

Plan ahead

You do need to plan for any unforeseen emergencies, such as delayed arrivals that may affect if and when you can dialyze. Before you travel, talk with your dietitian about emergency supplies to keep with you at all times, including all medications as well as recommended foods to eat or avoid.