How to Decide If Phototherapy for Eczema Is Right for You

Considerations before and after treatment

While not a first-line treatment, phototherapy may be used for eczema when other methods, like topical steroid creams and medications, fail to improve symptoms.

The treatment consists of exposure to a therapeutic light source, typically ultraviolet light. It can also be used for other skin disorders, like psoriasis, and vitiligo

hands of a patient with psoriasis close-up under an ultraviolet lamp

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Does Light Therapy for Eczema Work?

Ultraviolet radiation used in phototherapy has the potential to improve the symptoms of inflammatory skin conditions by decreasing the production of cytokines, proteins produced by certain cells of the body that can cause many autoimmune conditions, including inflammation.

What Are Cytokines?

Cytokines are small proteins that are crucial in controlling the growth and activity of blood cells and immune system cells. Cytokines affect the growth of all blood cells and other cells that help the body's immune and inflammation responses. When released, they signal the immune system to protect the body from threats.

Ultraviolet radiation also has the potential to protect the skin by thickening the outermost layer to prevent entry of external substances and bacteria.

Relief from Eczema Symptoms

Symptoms of eczema include skin redness, dryness, itching, and pain. Because the integrity of your skin is compromised, skin affected by eczema is at an increased risk of bacterial, viral, and fungal infections. Phototherapy can help relieve some of these symptoms by decreasing inflammation that can cause redness, itching, and pain and by protecting against infections by destroying external pathogens. 

Types 

There are several forms of phototherapy used to treat eczema based on the light wavelength used. The length of the light wavelength determines how deeply the light is able to penetrate into the layers of skin. Ultraviolet (UV) radiation used for the treatment of inflammatory skin conditions like eczema is typically in the UVB (ultraviolet B) range of 290–320 nanometers in wavelength to the UVA (ultraviolet A) range of 320–400 nanometers in wavelength.

UVB radiation can be divided into two different types: broadband UVB, in which the treatment wavelength increases with each visit, and narrowband UVB, which utilizes a restricted wavelength range. Narrowband UVB, which is 311–313 nanometers in wavelength, causes much less skin redness than broadband UVB and is more effective in decreasing the symptoms of eczema, leading to rapid remission of symptoms.

UVA penetrates deeper, which may be effective for thicker plaques, raised, inflamed and scaly patches of skin, while UVB penetrates more superficially (closer to the surface of the skin).

UVA phototherapy can also be used in combination with psoralen, a plant-derived medication that makes your skin more sensitive to light, to increase the effectiveness of phototherapy.

Excimer laser may also be used. It is focused narrowband ultraviolet B (NBUVB) for small focal areas of eczema.

The risk of skin cancer and photodamage is much higher with UVA than UVB light, so UVA is now rarely used and UVB is more commonly used.

When to Try UV Light Therapy 

The American Academy of Dermatology recommends using UV light therapy as a second-line treatment for eczema when first-line treatments like topical steroids, topical calcineurin inhibitors, drugs that alter the immune system, and emollients fail to improve symptoms.

It can also be used as maintenance therapy to prevent the progression of eczema when needed. UV light therapy should only be performed under the guidance and ongoing supervision of a physician.

While dosing of phototherapy intensity and frequency of scheduled visits can vary case by case, phototherapy typically is used three to five times a week for four to eight weeks.

Getting a Referral

If your eczema is responding to other treatment methods, your doctor may refer you for phototherapy treatment. Phototherapy is usually performed in a hospital clinic. Many insurance companies cover phototherapy and consider it medically necessary for refractory eczema that does not improve with other treatments.

Services are generally covered by insurance for two to three sessions a week for up to 23 weeks. After 23 weeks, services are usually only covered once every three weeks for maintenance. If no improvement occurs after two months, treatment is discontinued and no longer considered medically necessary.

If you continue to benefit from phototherapy and your therapy is considered medically necessary, you usually can continue treatment beyond 52 weeks, for up to 200 total treatment sessions.

During Your Appointment

Your first few treatments will be very short, starting at less than a minute and increasing in duration with each session, up to 30 minutes. Treatment is gradually increased incrementally to make sure you tolerate the treatment without adverse reactions. 

During your treatment, you will be positioned under a special ultraviolet lamp for the duration of the treatment, exposing the area of your body to be treated. Make sure you wear loose clothing that can be pushed up and out of the way during treatment. Your skin will need to come in direct contact with the light.

You will wear protective goggles during your phototherapy treatment to protect your eyes from the ultraviolet radiation. If your treatment is combined with psoralen treatment, you will also have to wear protective goggles for 12 to 24 hours after treatment since your eyes will be extra sensitive to light.

Skin dryness is a common side effect of phototherapy treatment, so regular application of an emollient after treatment is recommended. Depending on your doctor's recommendations, you may need to apply emollient one hour before treatment to help prevent excessive skin dryness.

While you are undergoing phototherapy treatment, it is important to avoid any additional exposure to ultraviolet radiation from sunlight or tanning beds as your skin will be extra sensitive and this increased light exposure can cause severe burning and damage to your skin. You will also need to wear sunglasses before and after your treatment sessions.

Tanning beds should always be avoided. The amount of ultraviolet radiation emitted from tanning beds is unregulated, and regular use increases your risk of skin cancer. Using a tanning bed is not the same as receiving phototherapy treatment.

Possible Benefits vs. Risks 

Based on the guidelines for using phototherapy from the American Academy of Dermatology and due to lack of studies, small sample sizes, and different dosing parameters, no conclusions can be made regarding what specific form of phototherapy is best for treating eczema. Narrowband UVB phototherapy, however, is most commonly recommended because of its relative effectiveness, availability, tolerance, and low associated risks.

Phototherapy typically has a low risk of side effects, but potential side effects may include redness, tenderness, itching, burning, hyperpigmentation, which refers to darkened patches or spots on the skin, and skin dryness.

Caution should be taken with patients who take medications making them sensitive to light, such as topical calcineurin inhibitors, since these patients may be at an increased risk of side effects posed by phototherapy. Using psoralen with UVA treatment also increases the risk of patients developing headaches, nausea, vomiting, and sensitivity of the skin and eyes to light.

Patients should receive regular skin checks during and after phototherapy as the risk of developing skin cancer during or after treatment remains unknown.

Summary

Phototherapy may be recommended if other forms of treatment for eczema do not improve your symptoms. It involves exposing your skin to ultraviolet light, which can potentially decrease the production of cytokines. Cytokines are proteins that trigger the immune system response and lead to inflammation in conditions like eczema. You will need to wear sunglasses before and after your treatment sessions.

A Word From Verywell

Because eczema may affect everyone differently, phototherapy may or may not be effective for you. First-line treatment options like topical steroid medication should always be tried first before attempting phototherapy.

If your eczema symptoms do not improve after initial treatment, phototherapy may be an option worth trying if your doctor thinks you're a good candidate. While phototherapy cannot cure your eczema, it may help to decrease your symptoms and improve your quality of life. 

Frequently Asked Questions 

How effective is phototherapy for eczema?

The effectiveness of phototherapy can vary, but it usually is tried for two months. If patients experience improved symptoms after two months, services may be continued indefinitely for maintenance of symptom improvement. Phototherapy is discontinued after two months if no improvement has been seen. 

Is phototherapy for eczema covered by insurance?

Phototherapy for eczema is covered by insurance when other treatment options have failed to improve symptoms. 

How safe is light therapy for eczema?

Light therapy for eczema is generally safe, with a low risk of side effects, although increased skin sensitivity, redness, itching, and dryness can occur. 

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  3. Prasad S, Coias J, Chen HW, Jacobe H. Utilizing UVA-1 Phototherapy. Dermatol Clin. 2020 Jan;38(1):79-90. doi:10.1016/j.det.2019.08.011

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By Kristen Gasnick, PT, DPT
Kristen Gasnick, PT, DPT, is a medical writer and a physical therapist at Holy Name Medical Center in New Jersey.