You know that the sun increases the risk of skin cancer for most people. You probably don’t know that for some people, the sun is the source of a terrible itchy rash — they’re allergic to the sun.
The radiation from the sun triggers some response in everyone’s skin. In some, the radiation triggers an immune reaction, leading to red, itchy, burning bumps. There are several diseases that are caused by sun which lead to rashes. Here are a few:
Polymorphous Light Eruption (PMLE): This is the most common. It is usually characterized by tiny, itchy red bumps that develop on the arms, neck and face hours after sun exposure. It is often seen in the spring and occurs more frequently in young people.
Actinic Prurigo: This is seen as itchy red bumps that occur mostly in children who are sensitive to the sun. Like PMLE, it occurs mostly on the face (including lips), arms, and hands. It can be more severe than PMLE and can lead to scarring in rare instances.
Chronic Actinic Dermatitis: This usually affects adults. It starts in areas exposed to the sun, but can spread to other areas. It is often terribly itchy and can be triggered by sunlight even though car windows.
Solar hives (urticaria): These are itchy pink whelts that develop within minutes of sun exposure. The rash develops quickly and fades quickly but can be intensely itchy. Antihistamines such as Zyrtec (ceterizine) or Benedryl (diphenhydramine) can help.
There are other sun-induced diseases, including ones triggered by medications. I’ll write about them in a future post. In all of these conditions, the most important thing to remember is to avoid sun exposure as much as possible. If you develop an itchy or burning rash after sun exposure, then see your physician for an exam and for advice.
Photo: Sandman (flickr)