Psoralen Plus UV A (PUVA) Light Treatment for Alopecia Areata

Alopecia areata has been treated with Psoralen Plus UV A light (PUVA) since 1974. PUVA is a treatment that utilizes photo chemotherapy. The therapy uses a drug called psoralen, a drug found naturally in plants, that is given either orally or topically, then ultraviolet A radiation light exposure. Psoralen has a chemical called 8-methosypsoralen (8 MOP) that is sensitive to the light. It turns the skin photosensitive which enhances the UV A light's effects. Psoralen has been used to cure a variety of skin diseases.

Effects of treatment through PUVA

PUVA was previously used to treat skin problems like vitiligo, psoriasis and eczema. PUVA has many effects that make it effective including:

PUVA is important in the treatment of alopecia areata because of its photo immunologic effects T-cells. The other effects listed above cause PUVA to be an effective treatment option for alopecia areata. There is more and more evidence that support melanocytes playing a major role in alopecia areata. Also studies show that oral treatments in PUVA are more effective than topical. Possibly because of the changes that occur internally in the immune system.

Application of treatment

The first phase of PUVA treatments involves the administration of an initial oral or topical dose of psoralen followed by exposure to UV A radiation lights. The radiation produced from UV A rays has a high intensity and its source of radiation is artificial. On a case by case basis, the exposure is done to either the entire body or just the area effected by alopecia areata. The UV A light come from either a hexagonal or square light box that contains fluorescent tubes that put off the UV A light rays. The length of the exposure is slowly increased over the course of the treatments.

Results of treatment

PUVA has given mixed results in several studies. When the conditions are uncontrolled the success rate is 40% to 50% of participants. However, since they were uncontrolled studies, it makes it hard to decipher exactly how genuine these results are or how many go into remission. Some findings suggest that the remission rate of these studies is as high as 40% after the PUVA treatments were stopped. Why there are so many relapses is not known, but one theory suggests that as new hair grows, it blocks the UV A rays from penetrating the skin.

One study was done over five years on 23 patients. The severity of their condition varied. They were given their UV A exposure in a stand up light box that was putting off 320-200 nm strength rays with fluorescent tubes. 20 of the patients received oral doses of 8 MOP ranging from 10mg-60mg, depending on body weight, two hours before exposure. Of them, 3 had only their scalps exposed, while the remaining 17 had full body exposure. The other 3 of the 23, who had the most severe cases, were given a topical .1% 8 MOP then only their scalps were exposed.

They all received the 8 MOP three times a week but the level was slowly increased each time. By the 30th treatment some hair growth was seen and between the 50th-80th treatments complete hair regrowth. Of the 17 of the first 20, 11 showed 90% or better hair growth. The other 3 of the 20 had failed treatments with the remaining 3 had partial hair growth. So according to this study the most effective is oral treatments followed by full body exposure.

Another similar study with 30 participants gave treatments for 7-9 months with one patient having full regrowth, 8 had moderate growth, 7 had just a minimal amount of growth and the remaining 10 had no change at all. Although everyone who had any results had relapses with in 7 months of the end of treatments. Most of the studies that have been conducted all show that the severity of the alopecia areata had no effect on the results.

A ten year study on PUVA was done by Taylor and Hawke that concluded that the success rate, that is those who obtained at least 90% of their hair regrown, in patients with patchy alopecia was 43% and those who had alopecia totalis had 50%. Although in this study if there was a relapse with in 4 months, those results were taken out of the study. For patchy alopecia the response rate was not satisfactory for 6.3% and 12.5% if they had alopecia totalis. The study concluded, as did all those before them, that PUVA was not effective for the long term treatment of alopecia areata.

Side effects

Because of the exposure to the UV A radiation rays, PUVA has a big risk of patients developing one of many kinds of skin cancers, with the fatal melanoma being the most common. This makes it vital that patients get ongoing post treatment follow up and monitoring for up to twice as long as the treatments lasted. If there is any type of abnormalities in the skin like odd colors, itching or pain, then a doctor should be contacted immediately. The most common side effect that was reported was nausea but there are also other minor side effects that include: sensitivity to sunburns, dizziness, headaches, skin that is red, darkening of the skin, premature aging and severe itching.

Conclusion

Due to the potentiality high risk of fatal cancer, PUVA is not suitable for the long term therapy of alopecia areata. Even with out these risks, the chances of relapsing so soon after the end of treatments also makes it a poor solution for long term hair regrowth.