Artificial or natural UVB rays may help reduce some symptoms of psoriasis, but it is important to take precautions to avoid sunburn.
The sun’s ultraviolet rays are made up of UVA and UVB rays. UVB rays may improve psoriasis symptoms by slowing the rapid rate of the affected skin cells.
It is important to remember that tanning for hours in the sun doesn’t cure psoriasis. There are risks. Most importantly, you should always take precautions to avoid sunburn.
Exposure to natural sunlight may help improve psoriasis. However, natural sunlight is not as effective as phototherapy, which can target affected skin and uses only UVB rays.
Certain psoriasis treatments, such as topicals containing tazarotene and coal tar, can also increase the risk of sunburn.
For the above reasons, it is important to talk with your doctor before you try sun exposure to treat psoriasis. For some individuals, as little as 5 to 10 minutes of sun exposure could result in a sunburn.
If you have mild psoriasis, about 30 minutes of exposure at noon may be a good start. People with more severe symptoms may want to start with less and increase their exposure time slowly, at their doctor’s discretion.
You should also still wear sunscreen with an SPF of 30 or greater, even when you want your skin to soak up the sun’s UVB rays.
Phototherapy is a treatment for psoriasis that uses natural or synthetic light.
Treatment with an artificial UVB source is most successful when administered for a set time on a regular schedule. Treatment can be done in a medical setting or at home with instructions from your healthcare provider.
In a medical setting, UVB treatment can involve:
- Localized units. These are small units for areas such as the hands and feet. There are full-body units and hand-held units. Some UVB units use UV lamps or bulbs, while others use LED bulbs.
- Excimer lasers. The laser can target areas of the skin affected by mild to moderate psoriasis, and it may be particularly effective for scalp psoriasis.
PUVA
Your doctor may choose to treat your psoriasis with UVA rays instead of UVB. UVA rays are shorter than UVB and penetrate your skin more deeply. Because UVA rays are not as effective in clearing the signs of psoriasis, a medication called psoralen is added to the light therapy to increase effectiveness.
You’ll take an oral form of the drug or use a topical prescription on the affected skin before your UVA treatment to help your skin absorb the light. Short-term side effects include nausea, itching, and redness of the skin. This combination treatment is generally abbreviated as PUVA.
PUVA is used to treat moderate to severe plaque psoriasis. It may be used when topical treatments and UVB therapy have not been successful. Thicker psoriasis plaques respond well to PUVA because it’s absorbed deeper in the skin. Hand and foot psoriasis are often treated with PUVA therapy.
It is important to note that individuals who are undergoing PUVA therapy should not expose themselves to natural sunlight unless otherwise directed by their healthcare provider.
Individuals with psoriasis may be more likely to have low levels of vitamin D, though it’s not clear how the vitamin is involved in the psoriasis disease process.
However, supplementing with vitamin D may not significantly improve symptoms of psoriasis. Research is mixed, and the National Psoriasis Foundation does not recommend oral supplements for treating psoriasis in adults with appropriate vitamin D levels.
Still, getting enough vitamin D
- fortified milk and orange juice
- certain fish, such as salmon and tuna
- fortified cheese and yogurt
- mushrooms treated with UV light
Exposure to natural sunlight may not be the most effective treatment for psoriasis. You may consider talking with your doctor about phototherapy to see if it is right for you.
If you do practice sun exposure, remember to limit your time in the sun and wear sunscreen.