UV radiation is widely accepted psoriasis treatment. PUVA, which stands for psoralen + UVA light radiation, is a variation of this method.
UVA light, like other kinds of UV light is invisible. It has longer wavelengths than UVB light and thus has a different effect on the skin. The drug psoralen, which can be administered as a cream or orally, increases the skin’s sensitivity to UVA light. In other words, psoralen causes your skin to soak up UVA rays much more than normal.
These two treatments working together are supposed to attack skin cells affected by psoriasis more vigorously than UV light would on it’s own, but the more I read about this treatment, the more it seems to be unhealthy as a long term treatment.
Since I am from Phoenix, I am accustomed to avoiding the sunlight as a general rule, taking in only sometimes and in only measured doses. For example, if I pull weeds with no sun block on the back of my neck, I will get at least a mild sunburn within about a half hour (and I don’t burn easily compared to most people).
So, being a Phoenician, it is difficult for me to believe that soaking up so much UV light can be a good idea overall (though it may kill some psoriasis symptoms for a least a little while). My inclination is that regular old sunlight is strong enough — I would worry about the damage being done to my skin cells from amplified sunlight. I don’t like psoriasis, but skin cancer might be worse.
One of the most discouraging side effects of psoralen is nausea, which can be offset by other natural remedies. Other side-effects include headaches, redness, itching (more itching?!), and severe sunburns / blistering.
One of the most common forms of psoralen is a medicine called “Oxsoralen Ultra.”