PUVA treatment
Psoralen (methoxsalen) is given orally or topically (via lotion or bath) 1½ to 2 hours before the skin is exposed to UVA light. Psoralens given in bath causes greater sensitivity to UVA than the oral medication, so lower doses of UVA can be used. The PUVA combination treatment is repeated 2 to 3 times a week. As treatment progresses, the dose of medication is not increased, but the amount of light may be increased.
Mechanism
PUVA therapy reduces the excess growth of skin cells. Psoralens increase the skin's sensitivity to UV light and thus improve the effectiveness of UV light therapy. PUVA is used to treat moderate to severe psoriasis (covering more than 20 % of the skin) that has not responded to other treatments. It should be used in the lowest doses possible since higher doses and more exposure increase the risk of skin cancer.
Psoralens should not be used by:
- Children under age 12.
- People who have diseases that make their skin more sensitive to sunlight (such as lupus).
- Fertile men and women who do not use birth control.
- Pregnant women, because of possible effects on developing fetuses.
Side Effects
Short-term side effects when using PUVA to treat psoriasis include:
- Skin redness, headache, nausea, itching, burns
- The spread of psoriasis to skin that was not affected before
- Nausea from the medication
- Squamous cell carcinoma or melanoma
Long-term side effects when using PUVA to treat psoriasis include:
- Premature skin damage associated with sun exposure
- Discolored spots on the skin
- Actinic keratosis
- Nonmelanoma skin cancer
- Cataracts (Cataracts may be avoided by wearing goggles during treatments and UV blocking sunglasses outdoors for the first 24 hours after treatment).
- Weakened immune system
Phototherapy Products Available with UVA
