Photopheresis is a procedure that changes blood cells called lymphocytes to help them fight cancer or calm your immune response. During photopheresis, a machine removes your lymphocytes and treats them with UVA light before they’re returned to you. Photopheresis treats some forms of cancer, graft versus host disease and organ transplant rejection.


What is photopheresis?

Photopheresis (pronounced “FOH-toh-feh-REE-sis”) is a procedure that uses light to change your white blood cells called lymphocytes. Your lymphocytes play an important role in your body’s immune response by destroying cancer cells, bacteria and viruses. Photopheresis can help if there’s a problem with your lymphocytes.

By changing your lymphocytes, photopheresis can strengthen or weaken your immune response. It can activate your lymphocytes to fight harmful cells (like cancer cells). Photopheresis can also prevent lymphocytes from attacking cells in your body (like in graft versus host disease in a bone marrow transplant).

Photopheresis is also called extracorporeal photoimmunotherapy (ECP) or photochemotherapy.

What is photopheresis used for?

Photopheresis is a form of immunotherapy, a treatment that uses your immune system to fight certain conditions.

Photopheresis may be used for:

  • Cutaneous T-cell lymphoma (CTCL): Photopheresis was developed in the 1980s as a treatment for CTCL. CTCL is a rare form of blood cancer that affects your skin. Photopheresis is currently used to treat two types of CTCL, Sézary syndrome and mycosis fungoides.
  • Graft versus host disease (GVHD): Your provider may give you photopheresis as a treatment for GVHD if other first-line treatments, like corticosteroids, aren’t working. With GVHD, the donated stem cells you receive following an allogeneic bone marrow transplant view your body as foreign and start attacking it. Photopheresis slows or stops the attack.
  • Organ transplant rejection: Your provider may give you photopheresis after a major organ transplant (like a lung, liver or heart) to prevent your body from rejecting the organ.

Other conditions your healthcare provider may treat using photopheresis include:

How can photopheresis help me?

Treating your lymphocytes during photopheresis changes the way they work. When the treated lymphocytes are returned to your body, they’ll stimulate an immune response in your body to fight cancer cells or slow the progression of GVHD. They’ll prevent your body from attacking a new organ. Photopheresis can also help relieve the symptoms associated with these conditions.


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Procedure Details

How do I prepare for photopheresis?

Your healthcare provider will explain what steps you need to take to prepare. They may recommend that you:

  • Drink plenty of fluids (at least eight glasses a day) for two days before treatment to help promote blood flow. This will make it easier to draw blood during the procedure.
  • Avoid caffeine and alcohol to prevent dehydration, which can slow your blood flow.
  • Avoid high-fat foods (like fried foods and desserts) that can make it more difficult for the machine used during photopheresis to separate your blood components.

How is photopheresis done?

Photopheresis separates your lymphocytes from the rest of your blood, treats the lymphocytes and then returns the treated blood cells (along with the rest of your blood) to you.

During the procedure:

  1. A healthcare provider will take blood from a vein in your arm or chest through an IV or a thin plastic tube called a catheter. You may receive a sedative or topical anesthetic to prevent pain or discomfort.
  2. The blood will enter into a machine that separates your lymphocytes from the other components of your blood, like red blood cells, platelets and plasma.
  3. The machine will add a substance called 8-methoxypsoralen (8-MOP) to your white blood cells. 8-MOP is a safe, plant-based substance that activates when exposed to light.
  4. The lymphocytes mixed with the 8-MOP will be exposed to ultraviolet A (UVA) light inside the machine. The light will activate the 8-MOP, which changes how the lymphocytes function.
  5. Your blood — including the treated lymphocytes — will be re-infused back into your body.

The lymphocytes will either be activated to fight cancer cells or deactivated so they don’t launch an immune response to fight healthy stem cells or a new organ.


What happens after the procedure?

A healthcare provider will check your pulse and blood pressure and ask how you feel. You can go home if your vital signs are normal and you’re not experiencing side effects.

How long does photopheresis last?

The photopheresis process lasts about three to four hours. You may need several photopheresis sessions before your condition improves. For example, you may need weekly or biweekly treatments at first and then fewer treatment sessions as your symptoms improve.

Your healthcare provider will develop an individual treatment plan based on your condition.


How will I feel during the photopheresis process?

You’ll lie comfortably in bed during the photopheresis procedure while your blood is taken, processed and re-infused. Photopheresis is a painless procedure.

During the procedure and immediately after, you may notice symptoms similar to giving blood. Changes in your blood volume might cause you to feel dizzy, light-headed, cold or nauseated. Tell a healthcare provider if you experience any of these symptoms, and they’ll help relieve your discomfort.

Risks / Benefits

What are the side effects of photopheresis?

Photopheresis is considered a safe procedure. Most people don’t have side effects.

You may experience a slight drop in blood pressure during the procedure. If this is the case, you may receive intravenous fluids to return your blood pressure to normal.

Other possible side effects include nausea, skin redness, dizziness and fever about six to eight hours after the procedure. Tell your healthcare provider if you have a temperature over 100 degrees Fahrenheit (37.77 degrees Celsius). They might recommend you take medicines such as acetaminophen (Tylenol®).

Recovery and Outlook

What precautions should I take after treatment?

Photopheresis makes you more sensitive to the sun. To protect yourself, avoid sunlight, including indirect sunlight, for 24 hours after each session. Indirect sunlight includes light coming through a window, blinds or a curtain.

If you go outside, cover your skin and wear sunscreen with at least SPF 30. Wear UVA protective sunglasses in a “wraparound” style to protect the sides of your eyes. UVA sunglasses are available in many colors, including clear, at most drug stores. You should wear these inside and outside for 24 hours after each photopheresis treatment session.

How long does it take for photopheresis to work?

Response times vary depending on your condition and your treatment schedule. For example, some studies have demonstrated that people with chronic GVHD experience improvements within three or four months of receiving photopheresis. On the other hand, people with scleroderma may need six to 12 months of treatment before symptoms improve.

Ask your healthcare provider how quickly you can expect results based on your condition and treatment frequency.

A note from Cleveland Clinic

Photopheresis is a safe, painless procedure that can help your lymphocytes and immune system work better. It may take some time to notice improvements, but many people with cutaneous T-cell lymphoma (CTCL) and graft versus host disease (GVHD) have benefited from this treatment. Unlike some other therapies, it doesn’t typically cause side effects. Ask your healthcare provider how frequently you’ll receive photopheresis and how much time it will take to notice changes in your condition.

Medically Reviewed

Last reviewed on 11/14/2022.

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