Polymorphic light eruption
Overview
Polymorphic light eruption (also called polymorphous light eruption) is a skin rash that can happen after being in the sun. It usually goes away on its own if you stay out of the sun, but it can keep coming back.
Symptoms
The main symptom of polymorphic light eruption is a rash on the skin. It usually appears within a few hours or days of going in the sun, and is more common in spring and summer. The rash may: have small raised spots or blistershave larger blotchy areasbe itchy or feel like it's burningbe red or pink – this may be harder to see on brown or black skin The rash can appear anywhere on the body, but is often in places that are not regularly exposed to the sun, such as the arms, legs or chest. A similar type of rash on the ears can cause small blisters that may be itchy or uncomfortable. This is called juvenile spring eruption.
Causes
Polymorphic light eruption is caused by a reaction to sunlight. It's more likely to happen when your skin is exposed to strong sunlight for the first time in a while, such as in spring or early summer, or when visiting a sunny country. The rash may come back every time your skin is exposed to sunlight. But as the summer goes on, your skin becomes more used to sunlight and it's less likely to happen. You're more likely to get polymorphic light eruption if you're under 40 years old, a woman or you have white skin. Boys aged 5 to 14 years are more likely to get a type of polymorphic light eruption called juvenile spring eruption that affects the ears.
Treatment
Polymorphic light eruption usually does not need any treatment. If your symptoms get worse or do not go away, treatments you may have include: steroidtablets or medicine you apply to your skin such as creams, lotions or gels (topical corticosteroids)antihistaminesphototherapy (light therapy) Your GP may be able to treat you or they may refer you to a skin specialist (dermatologist).