What Is Phototherapy? | Types | What To Expect | Effectiveness | Side Effects | Get Support

Phototherapy — also known as light therapy — is an effective treatment for atopic dermatitis (AD), an inflammatory skin disease. About 70 percent of people with eczema experience temporary or complete remission with phototherapy.

Atopic dermatitis is the most common type of eczema, affecting up to 20 percent of children and 3 percent of adults worldwide. Shining a light on troubled skin has provided relief from the itchy and uncomfortable symptoms of AD for many people, including members of MyEczemaTeam.

“I finished light therapy treatment two months ago and honestly, I have beautiful skin for the first time in years,” shared one satisfied member. Another said, “Phototherapy worked great for me. It took one year of twice-weekly trips for treatments, but the end result was spectacular!”

Phototherapy, however, doesn’t work for everyone. It also has risks. “I get a sunburned face that’s itchy as hell for a few days,” said one member. Another reported, “My eczema went away completely, but came back right after I finished light treatment.”

What Is Phototherapy for Atopic Dermatitis?

Phototherapy is a second- or third-line treatment for chronic or acute AD in children and adults. The therapy is typically recommended for moderate to severe eczema that doesn’t respond to conventional treatments, like topical steroids and biologics. Phototherapy is not recommended for photosensitivity dermatitis.

Phototherapy has been used for many years as a treatment for skin diseases and conditions. It works by repeatedly exposing affected skin to ultraviolet (UV) radiation — including natural sunlight or artificial light — to slow down or suppress inflammatory activity that causes AD flares. Use of an artificial light source, which replicates the sun’s UVA and UVB rays, has been found to reduce the number of T-cells that drive AD inflammation.

Light therapy can be performed on the whole body or specific areas where AD typically appears, such as the hands, head, and feet. It’s typically done in a special unit surrounded by fluorescent bulbs or under lamps that treat localized lesions. Phototherapy may be used alone or in combination with systemic and topical drugs. Skin generally improves after several weeks of treatments.

Types of Phototherapy for Atopic Dermatitis

Several types of light therapy are recommended for atopic dermatitis. Each has varying degrees of benefit.

Narrowband Ultraviolet B

A first-line, “gold standard” light therapy for chronic moderate-to-severe atopic dermatitis, narrowband UVB (NV-UVB) light uses the sun’s optimal wavelength to treat eczema. NB-UVB is preferred by doctors because it’s short-acting, cost-effective, and safe for use in children and pregnant people. NB-UVB has proven safer and more effective than other forms of light therapy because it uses a smaller amount of radiation at a higher dose and does not involve the use of photosensitizing medicine.

Psoralen Ultraviolet A

Another frequently prescribed light therapy, psoralen ultraviolet A (PUVA) is highly effective in treating severe atopic dermatitis. The skin is first made sensitive to light with a drug (Psoralen); UVA treatment follows. PUVA can be used on the whole body or localized areas. PUVA may be an option if NB-UVB phototherapy fails or if a relapse occurs after treatment.

UVA1

Considered one of the most effective forms of phototherapy for acute atopic dermatitis flares, UVA1 involves higher doses of UVA light than other forms of phototherapy. UVA1 uses longer exposures to penetrate the skin without burning. However, UVA1 is associated with side effects and long-term skin damage. It’s also more expensive, requiring special light boxes with cooling systems.

Laser Therapies

Various laser modalities — including excimer, light-emitting diode (LED), and pulsed dye lasers — are emerging as possible new treatments for localized AD. Studies of excimer laser treatment in people with AD have shown improvement in disease and quality of life. Because more research is needed, lasers are not currently recommended as an AD treatment.

What Should I Expect With Phototherapy?

Phototherapy is typically given in a medical or hospital setting, three to five times a week for a total of two to three months. One to two months of steady treatment is required before improvements can be seen.

Your doctor or dermatologist will first conduct a thorough physical examination and take a medical history to determine the benefits and risks of phototherapy for you. Skin type, history of skin cancer, and use of medications that might make skin more sensitive to light will be taken into consideration. A skin patch test — called minimal erythema dose (MED) testing — may also be ordered to determine your response to a particular UV light source.

During a phototherapy treatment, you’ll apply a moisturizing oil to the skin and stand in a light cabinet undressed except for underwear, goggles, and other protective gear for eyes and sensitive body parts. The treatment lasts just a few seconds or minutes initially, then slowly increases over time as your skin responses are monitored.

If improvement is seen after several months, your doctor may reduce the frequency of your visits or temporarily stop them to assess whether the eczema is in remission. If the treatment is successful, some people stay on a maintenance schedule of one to two times a week.

How Effective Is Phototherapy for Atopic Dermatitis?

Studies have shown that all types of phototherapy — including natural sunlight — have improved clinical symptoms of atopic dermatitis. Although the standards of care do not recommend a single best source of light therapy, clinical trials suggest that NB-UVB is superior to BB-UVB or UVA1 for clearing atopic dermatitis.

In a six-year study of NB-UVB use in children with atopic dermatitis, 40 percent experienced complete clearance or reduced disease activity, as well as an average three-month remission. Another study of 21 adults observed a 68 percent reduction in AD symptoms and an 88 percent decrease in topical steroid use. Systemic PUVA has also proven effective in treating severe AD, but it requires extensive exposure. Long-term use is discouraged for AD due to a lack of safety studies, as well as potential risks and side effects of extended treatment.

Natural sunlight is still used therapeutically in many parts of the world today, called heliotherapy. Studies have shown that artificial light achieves better results than natural sunlight. However, one member of MyEczemaTeam said, “Light treatment did absolutely nothing. Being out in natural sunlight helped me more.”

Members of MyEczemaTeam have shared a range of experiences with phototherapy:

• “Phototherapy cleared atopic dermatitis on my hands, but the skin peeled off my fingers today.”
• “Some 35 sessions of phototherapy helped every part of my body except my face.”
• “Finished 22 PUVA treatments and in the end, still pretty raw, but only on my right foot. Will continue using my steroid cream to see how it goes over next week.”
• “I had chills and felt sunburnt. My doctor gave me a lower dose and I felt better. We all have different levels of relief and sensitivity.”
• “I usually get a few months’ break from flares after light therapy treatment. I changed from UVB to UVA recently and it vastly improved my skin.”

For best results, care guidelines recommend continued use of topical treatments (moisturizers, emollients, calcineurin inhibitors, and corticosteroids) during treatment. If eczema improves, steroid treatments may be reduced or stopped all together. However, moisturizing with emollients during and after treatment can help clear dry skin.

Side Effects and Risks of Phototherapy

Although phototherapy is considered safe, it carries the same risks as overexposure to the sun.

Common side effects include:

• Skin discoloration and tenderness
• Sunburn
• Dry skin
• Actinic keratosis (rough, scaly patches that are precancerous)
• Premature skin aging (brown spots and wrinkles)
• Sensitivity to sunlight

Less common side effects, mostly from UVA1 and PUVA treatment, include:

• Brown patches
• Skin rash
• Hyperpigmentation
• Inflamed follicles
• Nail bed separation (PUVA)
• Pruritus — Discolored rough or bumpy skin (UVA1)
• Reactivation of herpes simplex virus (UVA1)
• Signs of systemic toxicity (PUVA)

More serious side effects include:

• Melanoma
• Nonmelanoma (basal cell carcinoma, squamous cell carcinoma)
• Headaches and nausea (PUVA)
• Cataracts from insufficient eyewear during treatment (UVA)

All UV treatments, especially PUVA, carry a long-term risk of developing skin cancer, especially for people with fair skin. Careful evaluation is necessary before initiating any UV phototherapy. Some researchers recommend avoiding phototherapy for children or reserving it for the most severe or treatment-resistant cases.

Phototherapy has other drawbacks, including the cost and frequency of treatment and whether treatment centers are easily accessible. It can also be difficult to treat hard-to-reach or hairy areas (head, genitals, and skin folds in the armpit or groin).

Taking topical calcineurin inhibitors such as Protopic (tacrolimus) while undergoing phototherapy could be cause for concern. Manufacturers recommend limiting exposure to natural and artificial light sources while using topical medications.

Learn more about staying well with eczema. Find out how to avoid triggers, eat skin-friendly foods, and manage your emotional health.

Find Your Team

MyEczemaTeam is the social network for people with eczema. More than 39,000 people with eczema gather to share advice and talk about their experiences living with this skin condition. Phototherapy for atopic dermatitis is a popular subject.

What therapies have helped you find relief from the symptoms of eczema and atopic dermatitis? Have you tried phototherapy? Share your experiences in the comments below or on MyEczemaTeam.