Allergy to Ultraviolet A rays is also known as a sun allergy or photosensitivity. The sun's rays are made up of both UVA and UVB rays, and you can be allergic to one type individually or both. The allergy manifests when your body overreacts to exposure to sunlight, developing a rash, hives or blisters to exposed areas.
Types of Sun Allergies
Four types of sun allergies exist. If you develop a skin rash after a short exposure to sunlight, the cause could be polymorphous light eruption. This typically affects women between ages 20 and 40, according to Wellness.com, and most often strikes during spring and summer months. Symptoms lessen in severity as the seasons continue toward fall, but regain strength when it occurs again the following year. The hereditary version, actinic prurigo, is passed from parents to children, and is most common in American-Indians, according to Wellness.com. Symptoms, which similar to but less severe than PMLE, typically begin during childhood or early adolescence. A photoallergic eruption occurs when a chemical, such as sunscreen, cosmetics or ointments, is applied to the skin and the sunlight interacts with it. It can also occur if a medication is taken, such as oral contraceptives, antibiotics or an herb such as St. John's wort. The final type of allergy is solar urticaria, in which patients develop red, raised itchy hives on their skin after sun exposure. A sunburn is different than an ultraviolet ray allergy.
Whom it Affects
Anyone can develop an allergy to the sun, regardless of skin color, though people with light skin are more likely to develop the condition. However, men rarely develop polymorphous light eruptions, though it is not known why.
Cause
Ultraviolet radiation can cause changes in your skin's cell, causing an allergic reaction to occur. This change triggers your body's immune to attack proteins in your skin cells, releasing antibodies that cause the symptoms of the allergy. In some cases, the allergy is caused not by changes in your body's cells, but by chemicals in cosmetic products that you applied to your skins that are interacting with the UVA rays.
Treatment
Treatment varies depending on what type of allergy you have. A doctor might recommend over-the-counter corticosteroid creams such as Cortaid or prescribe a stronger form such as Kenalog. For a severe reaction, you might take an oral corticosteroid; however, these can cause serious side effects, so they are only used for a short period of time. Your doctor might also suggest an oral antihistamine to counteract the symptoms of an allergic reaction such as a rash or hives. Finally, you could undergo ultraviolet light therapy (also known as phototheraphy), where a specific type of lamp shines ultraviolet light on your body, helping your skin become accustomed to the ray and reducing symptoms of the allergy.
Living with an Allergy
If you think you have an ultraviolet ray allergy, avoid sun exposure as much as possible. When you go outside, cover your skin with long sleeves and wide-brimmed hats. If you are already having a reaction, apply a soothing skin remedy such as calamine lotion or aloe vera, and make an appointment with your doctor.
