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Photopheresis, also known as extracorporeal photopheresis (ECP), is a nonsurgical therapy that removes, treats and returns a patient's white blood cells.

The Apheresis Program at UC San Diego Health is the only outpatient therapeutic photopheresis center in San Diego County.

Cellex Machine

The Cellex is used for photopheresis.

Photopheresis involves removing blood through a needle or catheter and circulating it through a machine where the blood is separated into red cells, white cells, platelets and plasma. The white blood cells, which are responsible for immune response, remain in the photopheresis machine for treatment while the rest of the blood circulates back to the patient through a return needle.

A medication (methoxsalen) is added to the separated white blood cells and the cells are exposed to ultraviolet-A light (UVA). The light activates the medication, treating the cells. The treated white blood cells are circulated back to the patient through a return needle. 

What does photopheresis treat?

Therakos XTS used for photopheresis treatment at UC San Diego Health

The Therakos XTS is used for photopheresis.

Photopheresis is used to modulate the body's immune response system to make the immune system more tolerant. The treatment is used to treat: 

Potential side effects

Photopheresis is a safe procedure with a few possible side effects. You may have discomfort at the needle site and occasional light-headedness or nausea during treatment. Notify your nurse immediately if you experience any of these symptoms. Avoid direct and indirect sunlight and wear dark glasses for 24 hours after each treatment, as your eyes and skin will be temporarily more sensitive to sunlight.

Download a photopheresis patient handout to learn more or go to Patient Resources.

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