Prolonged and unprotected sun exposure can cause you to burn. You may learn your lesson and take precautionary measures the next time you venture outdoors. However, if you seem to burn or break out into a rash after minimal or protected sun exposure, this may signify a sun allergy. There are different types of sun allergies, and all can be diagnosed and treated by a dermatologist.
Causes
Sun allergies occur when your skin cells have an increased sensitivity to ultraviolet rays. Minimal sun exposure is usually tolerated by skin cells. However, if you have a skin allergy, your skin cells respond to sun exposure as they would to toxins by releasing antibodies. According to the Mayo Clinic, Caucasian and Native American women younger than 30 are most susceptible to sun allergy, though anyone can develop it--especially if sun allergy runs in your family. Sun allergies also develop when you take certain medications that increase your skin's sensitivity to sunlight.
Types
Merck outlines three types of sun allergies: chemical photosensitivity, polymorphous light eruption and solar urticaria. Chemical photosensitivity occurs when a medication causes your skin to burn easier than normal. Such medications include tetracycline antibiotics, sulfa-based medications and anti-inflammatory drugs, according to the Mayo Clinic. Polymorphous light eruption and solar urticaria are not attributed to medication-induced skin sensitivity. According to the Mayo Clinic, polymorphous light eruption is the most prominent form of sun allergy.
Symptoms
If you have chemical photosensitivity, the sun can cause your skin to become itchy, inflamed and discolored. Polymorphous light eruption causes itchiness, inflamed blood vessels and red bumps to form on your skin that look like acne. Solar urticaria causes hives, blisters and itchiness of the skin. The Mayo Clinic says solar urticaria symptoms can even occur on unexposed skin.
Diagnosis
Chemical photosensitivity generally desists once you stop taking certain medications, or when you decrease the amount of sun exposure while on such medications. Solar urticaria and polymorphous light eruption, on the other hand, are diagnosed by a dermatologist. The key to detecting sun allergies is the types of reactions you have to sunlight and how often they occur. Merck says your dermatologist may conduct a lupus test to see if your symptoms are related to lupus. Otherwise, a diagnosis is made by looking at your skin and how it correlates to sun exposure.
Prevention/Solution
Once diagnosed with a sun allergy, the best way to avoid skin reactions is by limiting sun exposure. The Mayo Clinic advises that you avoid sun exposure between the hours of 10 a.m and 3 p.m. Wear UV-protective clothing as well as a hat and sunglasses. Use sunscreen daily, even if you don't expect to be outdoors for long. If you reside in a region in which you venture outdoors primarily during the spring and summer, the Mayo Clinic recommends that you slowly build up a resistance to sunlight by going outside for a shot amount of time and then working your way up. Medical treatment of sun allergies includes the usage of oral or topical corticosteroids, antihistamines and ultraviolet light therapy.
