Types of Phototherapy continued...
It's generally used only in extreme cases or when other treatments haven't worked. You usually get 25 sessions of PUVA at your doctor's office two or three times a week.
Because psoralen drastically increases your body's sensitivity to light, it's important to protect your skin and especially your eyes after taking it. You should wear glasses that block ultraviolet light and reapply sunscreen for at least 24 hours after treatment.
Lasers. These send out highly focused beams of light. The light affects only your psoriasis patches, not your healthy skin. This cuts down side effects and may lower your risk of skin cancer. You also need fewer treatments compared to other types of phototherapy.
One type of laser, the excimer laser, uses focused high-energy ultraviolet B light. Studies show that psoriasis treated this way improved quicker than patches treated with other types of phototherapy. You usually get this treatment in your doctor's office twice a week for 4 or 5 weeks.
The side effects from laser therapy are generally mild, although some people feel pain. You may also have bruising, sunburn, and maybe scarring at the spots where you've been treated.
After treatment with lasers, you should avoid sunlight and be careful not to injure the area that was treated. If any blistering appears, call your doctor.
A Warning About Phototherapy
If you're using any kind of phototherapy, including natural sunlight, you should always make sure that you're not being exposed to risky levels of ultraviolet rays. Getting too much light is easier than you might think. For instance, if you're using UVB or PUVA, you shouldn't sun yourself in the yard or even go out for a walk without sunscreen. Also, during an artificial light session, make sure to use sunscreen or clothing to cover up areas of skin that don't need treatment.
Many medications, supplements, foods, and perfumes can increase your sensitivity to light, including some high blood pressure drugs, antibiotics, St. John's wort, and even celery. Be careful to avoid these when you're getting phototherapy. Also, if you're using phototherapy, especially PUVA, you should have regular skin exams to check for signs of skin cancer.