Polymorphic light eruption
How big a problem is it?
The skin rash may be a rare occurrence, or may happen every time the skin is exposed to sunlight. It ranges from mild to severe.
Sometimes, as little as 30 minutes of sun exposure is enough to cause the problem,and it can develop even through window glass or thin clothing.
However, for most people with polymorphic light eruption,the rash develops after several hours outside on a sunny day. If further sun is avoided, the rash may settle and go without a trace within a couple of weeks. It may or may not return when skin is re-exposed to sunlight.
If the skin is exposed to more sunlight before the rash has cleared up, it will probably get much worse and spread.
For many affected people, the skin rash appears every spring and remains a problem throughout summer, settling by autumn.
Medically Reviewed by a doctor on 21 Dec 2018
Introduction
Polymorphic light eruption is a fairly common skin rash triggered by exposure to sunlight or artificial ultraviolet light. It lasts for up to two weeks, healing without scarring.
What does the rash look like?
The rash can take many different forms (known as being "polymorphic"): most people getcrops of 2-5mm pink or red raised spots some people get blisters that turn into larger, dry red patches (looks
How big a problem is it?
The skin rash may be a rare occurrence, or may happen every time the skin is exposed to sunlight. It ranges from mild to severe. Sometimes, as little as 30 minutes of sun exposure is enough to cause
Who's affected?
Polymorphic light eruption is more common in women than men. It particularly affects those who are fair, although it can affect those with dark skin. It usually starts from the ages of 20 to 40, alth
What is the cause?
Polymorphic light eruption is thought to be caused by UV light altering a substance in the skin, which the immune system then reacts to, resulting in the skin becoming inflamed. Polymorphic light eru
How is it treated?
There's no cure for polymorphic light eruption, but careful avoidance of the sun and using sunscreens will help you manage the rash. Generally, avoid the sun between 11am and 3pm, and wear protective
What's the outlook?
Many people with polymorphic light eruption find the skin complaint improves over years the skin may harden (become more resistant to sunlight) during the summer, which means more and more sun can be
Subscribe
Ask the doctor
Rate this article
Find products