Light therapy or phototherapy, involves exposing the skin to ultraviolet light on a regular basis and under medical supervision. Treatments are done in a doctor’s office or at home with a phototherapy unit. The key to success with light therapy is consistency. Advanced phototherapy light treatments help patients reduce intense flare-ups that cause skin to become extremely itchy, red and irritated. Phototherapy has become an increasingly popular and effective treatment for psoriasis, eczema, vitiligo, and other skin conditions.
Ultraviolet Light B (UVB) Phototherapy
Present in natural sunlight, a type of ultraviolet light, called UVB, is an effective treatment for psoriasis, eczema, vitiligo and other skin conditions. UVB penetrates the skin and slows the growth of affected skin cells. Treatment involves exposing the skin to an artificial UVB light source for a set length of time on a regular schedule. This treatment is administered in a medical setting or at home. Used for more than 75 years, UVB phototherapy continues to be an effective treatment.
During Treatments: To receive UVB phototherapy, a person stands in a light box lined with UVB lights. UVB phototherapy usually takes place in a dermatologist’s office. If UVB therapy proves effective, some patients can use an at-home UVB unit prescribed by their dermatologist.
During treatment, your skin condition may worsen temporarily before improving. Your skin may redden and itch from exposure to the UVB light. To avoid further irritation, the amount of UVB administered may need to be reduced. Occasionally, temporary flares occur with low-level doses of UVB. These reactions tend to resolve with continued treatment.
Number Of Treatments: UVB phototherapy requires time. To be effective, 2 to 5 treatments per week are given for several weeks. The exact number of treatments varies with the patient’s response, type of UVB phototherapy prescribed, and the severity of the skin condition.
Some patients need to pre-treat their skin. Before stepping into the light box, most people apply a thin layer of petroleum jelly or mineral oil to the psoriasis. This thin layer makes the UVB light more effective.
How Long Clearing Lasts: Remission time varies. Recent studies suggest that it may be possible to increase clearing by continuing treatment for a bit after the skin clears. One such study found that more than half (55%) of the patients who did this were clear 1 year later. These patients received narrowband UVB phototherapy 3 times per week for 12 weeks. For the next 4 weeks, they received 2 UVB treatments per week. For the following 4 weeks, they received 1 UVB treatment per week.
Currently, most patients stop UVB phototherapy when their skin clears. Some begin the UVB treatments when the skin condition starts to return.
Home UVB Therapy: Treating your skin condition with a UVB light unit at home is an economical and convenient choice for many patients. Like phototherapy at your dermatologist’s office, it requires a consistent treatment schedule. Patients are treated initially at their dermatologist’s office and then begin using a light unit at home.
It is critical, when doing phototherapy at home, to follow your doctor’s instructions and continue with regular check-ups. Home phototherapy is medical treatment that requires monitoring by your doctor.
All phototherapy treatments, including purchase of equipment for home use, require a prescription. Some insurance companies will cover the cost of home UVB equipment. Vendors of home phototherapy equipment often will assist you in working with your insurance company to purchase a unit.
Psoralen + Ultraviolet Light A (UVA) Phototherapy
Like UVB, ultraviolet light A, called UVA, is present in sunlight. Unlike UVB, UVA is relatively ineffective unless used with a light-sensitizing medication called psoralen, which is administered topically or orally. This process, called PUVA, slows down excessive skin cell growth and can clear a variety of skin condition symptoms for varying periods of time. Stable plaque psoriasis, guttate psoriasis, and psoriasis of the palms and soles are most responsive to PUVA treatment.
Side Effects Of UVB and UVA Phototherapy: Your skin may be red, itchy, or dry after UVB and UVA exposure. Some people develop a sunburn-like reaction and sometime blister. Temporary worsening of your skin condition also is possible before your skin starts to clear. Pregnant women may develop melasma, a skin condition that causes mottled skin.
The most common short-term side effects of PUVA are nausea, itching and redness of the skin. Drinking milk or ginger ale, taking ginger supplements, or eating while taking oral psoralen may prevent nausea. Antihistamines, baths with colloidal oatmeal products, or application of topical products with capsaicin may help relieve itching. Swelling of the legs from standing during PUVA treatment may be relieved by wearing support hose.
Receiving years of UVB and UVA phototherapy may pose greater risks. Over time, exposure to UVB and UVA light may increase one’s risk of premature skin aging. Signs of premature skin aging include sagging skin, wrinkles, and dark marks. There also may be an increased risk of getting skin cancer. This is why sunscreen should be applied to all skin that does not require UVB and UVA phototherapy. All patients who receive phototherapy must closely be monitored by a dermatologist.