Sun rash, more properly known as photodermatitis, is an allergic reaction to light which causes the skin to develop a rash. The rash is typically reddened, thickened, and blistered, and it can be extremely itchy. Although a sun rash looks very similar to a sunburn, the root cause is different, and frequent rashes can be a cause for concern, as they may indicate the presence of a medical problem which has increased the body's sensitivity to light. You may also hear a sun rash referred to as “sun poisoning.”
Fair-skinned people are at increased risk of developing photodermatitis, but people of all skin colors can experience it. It can be caused by some medications, such as birth control pills, along with exposure to chemicals, certain foods, and some medical conditions, like lupus. People develop a sun rash because their skin has become extremely sensitized to light, and as a result it may take only a few minutes of exposure for a rash to develop. If the rash happens repeatedly, it can thicken the skin around the site, and sometimes lead to skin cancer.
Treatment for the condition is similar to that used for sunburns. Cool compresses can help with the itching and burning sensation, as can soothing lukewarm baths with oatmeal, baking soda, or cornstarch. Topical applications of calamine lotion, aloe vera, or hydrocortisone can also help ease the symptoms, and antihistamines can reduce the itching and swelling. If the rash breaks open, a trip to the doctor is recommended, as the patient may need antibiotics to prevent infections.
After someone gets a sun rash, it is a good idea to make a list of what he or she was exposed to in the day or so prior to the development of the rash, to see if any risk factors stand out. People who are taking medications which can cause photosensitivity are usually warned, but it's a good idea to check through the patient information packets on any medications in use, just to eliminate an obvious potential cause. If a pattern of rashes develops, it may indicate the patient needs to see a doctor to check for an underlying medical cause for the condition.
To prevent sun rash, people should wear sunscreen, hats, and sunglasses outdoors. Protecting the eyes during a period of photosensitivity is especially important, as sun exposure can cause damage to the eyes over a prolonged period of time. Loose-fitting clothing should be used to cover the body and keep cool in warm weather