How Does Phototherapy Treat Psoriasis?
- Phototherapy exposes patients with psoriasis to narrow band UVB light. This therapy is generally used when medications applied to the skin alone do not work and alternative options are needed.
- Patients generally start with a low duration of exposure, about 30 seconds. Then, in conjunction with your doctor, you build up to the maximum duration of time that you can safely tolerate.
- Phototherapy can be time intensive and financially cost prohibitive. Patients usually need treatment three times per week to begin.
Phototherapy for psoriasis is generally used as a second-line treatment when medications applied to the skin alone do not work and alternative options are needed. It can also be used for patients who wish to avoid medications that can affect their entire body (systemic medications). Phototherapy can also be used in conjunction with topical and/or systemic psoriasis treatments.
Read MorePhototherapy for Psoriasis: What you need to know
Phototherapy exposes patients with psoriasis to narrow band UVB light which penetrates the skin and inhibits DNA which in turn slows reproduction and reduces psoriasis plaques.As Dr. Khattri puts it "It's a limited spectrum of the sunlight, which we use. Patients generally have to come to a place that does phototherapy. There's a phototherapy box. You go there. It's generally three times a week in the very beginning until your psoriasis is in control. And beyond that, we can space it apart to once a week or twice a week as maintenance,"
A frequency of twice or three times weekly is effective and is recommended, according to the American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) guidelines.
The guidelines also recommend the application of a thin layer of petroleum jelly before treatment sessions. This increases treatment effectiveness in psoriasis and also reduces UV-induced rash.
Dr. George Han, a dermatologist at Northwell Health/Lenox Hill Hospital, says phototherapy is used less frequently for psoriasis now, mainly because there are so many effective medications.
"For phototherapy, people tend to have to come into the office two or three times a week to have the phototherapy done. So that is often challenging with work and school schedules,” he explains to SurvivorNet. “And each time they come in; they often have to pay a copay. So that actually becomes financially a burden as well."
Types of Phototherapies
There are many types of phototherapies available along with different instruments and lights to deliver the treatment. Your doctor will prescribe the treatment best suited for you depending on the following factors:
- Your overall health
- Your skin type
- Previous treatments taken
- Any underlying medical condition that you may have
- The severity of your psoriasis
- How much of the body is affected by psoriasis symptoms?
Below is a list of the most frequently described types of phototherapies by doctors:
UVB light. A patient stands in a lightbox for treatment or alternatively has a light source passed over their skin. This type of treatment includes two types: narrow-band and broad-band UVB.
Laser treatment. Laser is used specifically on the areas of psoriasis and delivers very high doses of light.
PUVA bath or pills. In this treatment, a medication called psoralen is used to make the skin more sensitive to UV light. In a PUVA bath, the patient soaks in psoralen, while in the case of PUVA pills the patient takes psoralen orally and then receives light therapy.
Light therapy for psoriasis at home. Treatment at home can be done by the patients on their own without help from the doctor where they can use instruments that help improve their symptoms. Examples of these instruments include handheld devices or at-home lightboxes.
Risks Associated with Phototherapy
Patients generally start with a low duration of exposure, about 30 seconds. Then, in conjunction with your doctor, you build-up to the maximum duration of time that you can safely tolerate. The risk of sunburn increases with too much exposure.
Even though phototherapy is considered generally safe, it can carry possible side effects on the skin that include the following:
- Red and tender skin
- Sunburn-like symptoms
- Burning
- Stinging
- Blisters
- Dark spots
- Burns
Other long-term side effects can include the following:
- Aging skin
- Freckles and skin marks or spots
- Wrinkles
- Loose skin
- Susceptibility to skin cancer
"If the patient gets a sunburn, then we scale back," says Dr. Khattri. "The downsides are that it's pretty intensive. The onus is on a patient to go to a unit, three times on average a week. And, certainly with one's busy schedule that might not necessarily always be feasible."
How Safe is Phototherapy?
American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) describe phototherapy as a "safe and well-tolerated intervention, as long as safeguards and cautions are implemented." Among the safeguards:
- Genital shielding is recommended in all patients during phototherapy sessions.
- Eye protection with goggles is recommended during treatment sessions to reduce the potential risk of harm to the eyes, including inflammation of the cornea and corneal burns.
- Studies have not found a direct correlation between phototherapy and an increased risk of skin cancer, but AAD and NPF guidelines suggest physicians should use caution in prescribing phototherapy for patients with a history of melanoma, multiple nonmelanoma skin cancers, arsenic intake, or exposure to ionizing radiation.
- Women of childbearing age receiving phototherapy should take folate supplements. (Phototherapy can deplete folate reserves, which are critical during pregnancy.)
You should keep all checkup appointments with your doctor and share any side effects, discomfort, or worsening psoriasis symptoms that you may be experiencing. These appointments are very crucial in your recovery.
Nevertheless, phototherapy shouldn't be used for patients who have the following conditions:
- Patients who are at a higher risk of developing skin cancer due to other health conditions
- Patients who had skin cancer
- Any underlying medical condition that causes skin sensitivity to UV light
- Patients who take medications that can make them more sensitive to UV light (ex. Of these medications: Antibiotics or diuretics)
Locating Phototherapy Providers
It's critical to note that not every dermatologist has phototherapy capabilities. "Phototherapy places can be a little challenging to find as they tend to be seen primarily in academic institutions," Dr. Khattri says.
However, the National Psoriasis Foundation's website can assist patients with locating a phototherapy provider. The National Health Care Provider Directory specifies providers with phototherapy machines.
Additionally, Phototherapy can be time-intensive and financially cost-prohibitive. Patients usually need treatment three times per week to begin, sometimes they may even need to go five times.
Phototherapy can require health insurance pre-authorization, notes Dr. Khattri, so it's important to allow the time it takes to contact your provider.
"In my experience, I've always had my patients have phototherapy covered as a treatment option," says Dr. Khattri. "It really comes down to whether there's like a deductible or a copay, or if the insurance is covering, say a fixed percentage of the visits. So that's the part where how much it costs you out of pocket would vary from person-to-person insurance to insurance."
Recommendations for Patients with Psoriasis Undergoing Phototherapy Treatment
- To achieve a better treatment response, you should maintain your sessions regularly and avoid missing out on any appointment
- You should refrain from using products that contain chemicals and can cause the skin to be irritated, these include products like deodorants, perfumes, or aftershave
- Inform your doctor immediately if you're starting any new medication
- Using indoor tanning beds is absolutely discouraged due to their association with causing skin cancer, aging, and damaging the skin
- Itchy and dry skin can be treated with creams and emollients so make sure to share with your doctor about any side effects or discomfort caused so they can prescribe the appropriate medication for you
If you're looking for more recommendations, precautions, and support for psoriasis, you can check out The Psoriasis and Psoriatic Arthritis Alliance.
Questions to Ask Your Doctor
- Is phototherapy a good option for treating my psoriasis?
- How does phototherapy work?
- What is the time commitment for my treatment?
- Is phototherapy combined with other types of treatment?
- How will I know if phototherapy is working to treat my psoriasis?
The Bottom Line
Phototherapy exposes patients with psoriasis to narrow band UVB light. This therapy doesn't cure psoriasis but it's very effective in managing the symptoms and improving skin plaques caused by the disease.
If you're thinking about trying out phototherapy, you should consult your doctor first to find out about the associated risks, potential benefits, and whether this treatment option is right for you.
Moreover, Phototherapy can be time-intensive and financially cost-prohibitive. Patients usually need treatment three times per week to begin, sometimes they may even need to go five times.
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