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Polymorphic light rash (sun allergy)

Polymorphic light rash (sun allergy) is a skin disease provoked by the sun’s UV rays and characterised by itchy rashes on the skin at the point of direct contact with the sun.

It usually occurs during the warm season (spring, summer), which means it is seasonal. Itchy, small, pink or skin-coloured papular rashes, less commonly plaques and vesicles, appear on areas of skin exposed to direct sun within a few hours, less often after a couple of days. Skin lesions disappear spontaneously within a few days if you avoid the sun.

Diagnostics:

The diagnosis is based on medical history (exposure to direct sunlight), clinical symptoms (itchy rash on sun-exposed areas of the body) and seasonality (warm season). In most cases, no further tests are needed.

Prevention:

– Sun protection: clothes that cover the skin, SPF 50 sunscreen
– Prophylactic phototherapy (narrow-wave UVB phototherapy) in early spring or late winter to increase tolerance to the sun’s ultraviolet rays during the warm season. The course is 2-3 treatments per week for 4-6 weeks each year.

Treatment:

– Corticosteroid ointments. They are effective in reducing inflammation and itching. These drugs are given for 5-7 days, 1-2 times a day.
– In advanced disease, oral corticosteroids are prescribed.

If you are unsure about your diagnosis and over-the-counter remedies from the pharmacy don’t help – seek help from a dermatologist!

The iDerma team will give you a consultation within 24 hours, explain your diagnosis and prescribe the necessary treatment remotely!