Sun allergy is a condition in which sunlight triggers a skin reaction. For most people, sun allergy symptoms include an itchy red rash in areas that have been exposed to sunlight. A severe sun allergy may cause hives, blisters or other symptoms. There are several types of sun allergy — including polymorphic light eruption (PMLE), actinic prurigo, chronic actinic dermatitis (CAD) and solar urticaria.
Sun allergy symptoms depend on the particular type of sun allergy you have.
When to see a doctor
Polymorphous light eruption on chest
Polymorphous light eruption occurs most often in areas that are covered in the winter months and exposed in the summer months, such as the front of your neck and chest. ...
Allergic reactions to sunlight occur when ultraviolet radiation triggers changes in your skin cells. These changes cause your immune system to mistakenly identify proteins in your skin cells as harmful invaders. Your immune system then releases antibodies that attack the cells, and this leads to symptoms.
For most people with a sun allergy, exposing bare skin to bright sunlight during the spring or summer triggers the allergic skin reaction. However, some people can have a reaction during winter months. In people who have a severe sun allergy, an allergic reaction may even be triggered by indoor lights.
Certain medications, chemicals and medical conditions can make the skin more sensitive to the sun (photosensitivity). For example, an ingredient in your shampoo or having a condition such as lupus can increase photosensitivity. In most cases this isn't a true allergic reaction. However, it can cause symptoms similar to those caused by a sun allergy — and if you already have a sun allergy, it can make your symptoms worse.
It isn't clear why some people have a sun allergy, and others don't. Inherited traits may play a role.
Risk factors for having an allergic reaction to sunlight depend on your particular condition. These include:
Sun allergy symptoms usually go away when the affected areas are protected from sunlight. They generally don't cause any long-term complications. However, in some people, severe actinic prurigo leaves pitted scars.
Preparing for your appointment
You're likely to start by seeing your family doctor or a general practitioner. However, when you call to set up an appointment, you may be referred to a doctor who specializes in skin conditions (dermatologist).
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared. Here's some information to help you get ready, and what to expect from your doctor:
Your time with your doctor is limited, so preparing a list of questions ahead of time will help you make the most of your time together. List your questions from most important to least important in case time runs out. For sun allergy, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your doctor
Tests and diagnosis
Your doctor will want to make sure your skin reaction isn't due to something other than a sun allergy. A number of conditions can cause similar symptoms. In some cases, a skin allergy can be diagnosed by answering questions or by having your doctor examine the affected areas when symptoms are present. However, if the diagnosis isn't clear-cut, you may need tests to help identify what's going on. If this is the case, you'll most likely need to see a dermatologist.
Tests to diagnose skin reactions caused by sun exposure can include:
Treatments and drugs
Treatment depends on the particular type of sun allergy you have. It may include:
Lifestyle and home remedies
These steps may help relieve sun allergy symptoms:
If you have a sun allergy or an increased sensitivity to the sun, you can help prevent a reaction by taking these steps:
Last Updated: 2010-04-29
© 1998-2014 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.com," "Mayo Clinic Health Information," "Reliable information for a healthier life" and the triple-shield Mayo logo are trademarks of Mayo Foundation for Medical Education and Research.
Terms and conditions of use