From healthcentral.com
Clearer skin and fewer office visits are just some of the perks. Discover how UVB therapy works at home
There are a ton of treatments out there for psoriasis, like topical creams, oral medications, and biologics. But few are as effective (or easy) as ultraviolet B (UVB) light therapy at home, which offers a more accessible way to use phototherapy—the use of a specific wavelength of light to help heal the skin—to treat a host of skin conditions, including psoriasis.
A Brief History of Healing Light
It’s not exactly new. UV light has been used since ancient Egypt to manage skin diseases, and in the early 1900s, the Nobel Prize was awarded to researcher Niels Finsen of Copenhagen for his development of medical phototherapy. More recently, in the 1980s, “we figured out that there’s a single wavelength of light, 311 nanometers, which is very effective at treating psoriasis—yet less likely to cause some of the harmful effects that you may see with other wavelengths that exist in sunlight,” says Joel Gelfand, M.D., a board-certified dermatologist and the medical director of the Psoriasis and Phototherapy Treatment Center at the University of Pennsylvania in Philadelphia.
The Biggest Barrier: Getting to the Dermatologist's Office (Again and Again)
Phototherapy has long been considered an effective way to treat psoriasis, especially compared to other common treatment options. In fact, one review found that it led 75% of people to achieve a status of “clear/minimal disease” with fewer topical treatments, such as steroid creams, for at least 12 months.
But access has been a huge issue, since individuals often must go to the doctor’s office two or three times a week for their phototherapy. “The treatments are [on average] a few minutes long, but to do it two or three times a week for eight to 12 weeks is really hard for a lot of people,” says Dr. Gelfand. Plus, he adds, your health insurer might view each session as a doctor visit and therefore charge a copay every time.
For those reasons, among others, the prospect of doing UVB light therapy at home is appealing—and becoming more common as the effectiveness of such at-home devices improves. In a 2024 study in JAMA Dermatology, of which Dr. Gelfand was the lead author, at-home phototherapy was as effective as the in-office treatment for people with plaque psoriasis. New York board-certified dermatologist Shari Lipner, M.D., a professor at the New York-Presbyterian Hospital/Weill Cornell Medical Center in New York City, also recommends them—especially for “some patients with psoriasis who may have trouble getting to the office during their school or workday,” she says.
What to Expect During At-Home Light Therapy for Psoriasis
At-home UVB light therapy might sound high-tech, but it’s surprisingly straightforward once you get the hang of it. Most people use a handheld or table-top narrowband UVB device that emits a targeted beam of light to treat psoriasis-affected areas. These machines come in different sizes—some are about the size of a shoebox; others resemble oversized flashlights—so you can either hold it directly over a patch of skin or rest it on a stand or table for hands-free treatment.
For larger surface areas or more severe psoriasis, some patients may use full-body panels or even walk-in booth-style units (similar to a tanning booth), though those are less common for home use. The distance between your skin and the light matters: typically, you’ll need to be about a foot away, but your doctor will provide exact instructions based on the device.
You’ll usually do treatments two to three times a week, for sessions ranging from 30 seconds to 15 minutes depending on your dose and skin type. Clothing is optional—many people expose only the areas being treated and keep the rest of their body covered for protection. The device is programmed to match your skin tone—whether fair, medium, or dark—and automatically adjusts the dose accordingly.
How do you know it’s working? According to Dr. Gelfand, a little redness about six hours after treatment that fades within 24 hours is a sign you’ve hit the sweet spot for effectiveness.
How Does UVB Light Therapy Work?
UVB light therapy can target specific areas on the body, which is why the ideal candidate is someone who has psoriasis on the arms, the legs, and/or the trunk, says Dr. Gelfand. It’s not as effective for areas like the scalp, genitals, or nails, where the light doesn’t penetrate as well. Done properly, light therapy offers a lot of benefits for skin. These include:
Slows skin cell growth. Psoriasis causes abnormally rapid skin cell turnover, leading to plaque formation. Broadly speaking, UVB light therapy “has an impact on the ability for the skin to proliferate rapidly,” says Dr. Gelfand. “It slows that down.”
Tames inflammation. UVB light seems to prevent something called “antigen presentation,” which occurs in conditions like eczema and psoriasis. In these conditions, the immune system mistakenly attacks normal proteins. UVB light therapy helps knock out the cells that trigger this immune response.
Restores skin colour. Having psoriasis may increase your risk of developing vitiligo because both are autoimmune conditions that can share similar genetic and immune system pathways. In vitiligo, the immune system attacks melanocytes—the cells that give skin its pigment. Research shows that UVB light can restore pigment by encouraging melanocytes to return to affected areas.
Boosts vitamin D. Vitamin D is a go-to treatment for psoriasis, but your body needs sunlight to make it. UVB phototherapy seems to do the trick, too. One study found that light therapy not only increased vitamin D levels but also improved skin clarity among people with psoriasis.
If you’re looking to try UVB light therapy at home, talk with your doctor first. “This really has to be done under supervision of a physician, preferably a dermatologist,” says Dr. Gelfand. “Most clinicians out there do not get the medical training necessary to diagnose and treat these types of disorders, nor do they have a strong background training of how to use ultraviolet lights effectively.”
Next, you’ll need a machine. You’ll find them in various sizes—handheld wands for small spots or full panels for larger body areas. Any reputable brand (Dr. Gelfand points to Phothera as a good one) will require a doctor’s sign-off in order to purchase. Avoid buying devices online without a prescription; the machines must be carefully calibrated to deliver safe, effective treatment.
What About Cost?
“The biggest barrier patients face is an uneven coverage of these devices by insurance,” says Dr. Gelfand. Sometimes they’re covered; sometimes not. Still, if you find phototherapy works for your psoriasis, it may be worth the investment: One study found phototherapy to be significantly more affordable than biologic treatments—averaging about $5,000 over three years, including bulb replacements compared to a single biologic injection that can cost $3,000 to $10,000.
Is At-Home Light Therapy Safe?
UVB light therapy at home is considered safe, especially because the devices come with built-in safeguards, and your doctor will program the right settings for your skin type.
In fact, in the JAMA Dermatology study, “no one had a severe-enough reaction to the light treatment that they decided to stop phototherapy,” says Dr. Gelfand. Still, it’s smart to be aware of potential side effects:
Burns. Possible but rare. “It’s pretty difficult to dose yourself in a way that you could have a medically significant burn because of how the machines are calibrated,” says Dr. Gelfand.
Skin cancer risk. While unlikely, long-term UV exposure could slightly raise the risk of skin cancer, especially in fair-skinned individuals. Dr. Gelfand recommends keeping unaffected skin covered—for example, roll up your sleeve to treat a forearm but keep the rest of your body protected.
UVB light therapy—especially at home—is one of the most promising treatments for people with psoriasis and other skin conditions. It can be life-changing, with some people reaching remission after just one course of treatment, says Dr. Gelfand.
Even if light therapy alone doesn’t do the trick, it’s an excellent first-line option. “Sometimes we combine therapies—we may add certain oral medications, we may add some of the newer topicals that can be very effective, or they may have to shift to some of the biologics,” he says.
And the best part? You can do it on your own time, in your own home—making it an empowering, flexible tool for managing chronic skin conditions.
