Dermatitis, Photoallergic

Dermatologist shines a light on the latest research in photocontact dermatitis SAN DIEGO, March 8, 2024 /PRNewswire/ -- Sun sensitivity and related skin conditions are often misunderstood. Foods, medications, and skincare products can trigger symptoms like itching, redness, blistering, or burning. One of the most common conditions is photocontact dermatitis, a skin reaction occurring when certain substances come into contact with skin that is exposed to the sun. "Sun sensitivity is a common condition that can negatively impact a person's quality of life," said board-certified dermatologist Brandon Adler, MD, FAAD, an assistant professor of dermatology at Keck School of Medicine at the University of Southern California in Los Angeles, speaking at the American Academy of Dermatology's 2024 Annual Meeting. For many people, sun sensitivity is caused by the things they come into contact with, said Dr. Adler. If you develop rashes, blisters, or skin darkening after making a margarita or chopping vegetables for a salad, some of the ingredients may be to blame, said Dr. Adler. Your skin reaction could be caused by handling fruits and vegetables such as lime, figs and celery, or coming into contact with plants like hogweed and St. John's wort. Certain pain relief medications that are applied to the skin may also cause a photosensitive reaction, as can medications taken by mouth, such as some blood pressure medications like hydrochlorothiazide. While medications applied directly to the skin only cause a rash in the area of the body where it was applied, if a medication taken by mouth causes photosensitivity, it can cause a rash over any part of the body that was not protected from the sun. Reactions often appear as an itchy rash or severe sunburn on areas of the body most exposed to the sun, such as the face, neck, arms, or legs, according to Dr. Adler. To determine the cause of sun sensitivity reactions, dermatologists must consider a variety of individual factors, such as various product exposures and medical history, and less frequently bloodwork or a biopsy of the affected area of the skin. "While we will often prescribe anti-inflammatory medications to treat photocontact dermatitis, the primary treatment is identifying and avoiding the irritant or allergen," said Dr. Adler. "In many cases these are reversible reactions, so if the patient stops using the substance causing the reaction, then they will stop having symptoms and won't need ongoing treatment." Many people incorrectly assume that certain types of sun sensitivity only affect older people with lighter skin types, but recent research indicates that younger people and those with darker skin types are more susceptible than previously believed, according to Dr. Adler. New studies suggest that people with darker skin types are susceptible to two other types of photosensitivity, he said. The first is polymorphous light eruption (PMLE), which appears as tiny bumps or rashes that come and go with sun exposure. The second is chronic actinic dermatitis, which causes year-round rashes affecting the sun-exposed parts of the body due to light sensitivity. The exact causes of PMLE and chronic actinic dermatitis are not fully understood, but they are believed to involve an abnormal immune response to sunlight. While it is important for everyone to protect themselves from the sun, Dr. Adler noted that those with sun sensitivity need to be particularly mindful to seek shade, wear sun-protective clothing, and apply a broad-spectrum, water-resistant sunscreen with an SPF of 30 or higher. "If you notice a rash or blistering on your body after being in the sun, it's important to see a board-certified dermatologist, who can determine whether you have a sun-related skin disorder," said Dr. Adler. "No two patients are the same. A board-certified dermatologist can determine what is causing your sun sensitivity and provide a treatment option that works best for your condition." To find a board-certified dermatologist in your area, visit aad.org/findaderm. More Information Eczema Types: Contact Dermatitis Causes AAD B-Roll Library About the AAD Headquartered in Rosemont, Ill., the American Academy of Dermatology, founded in 1938, is the largest, most influential and most representative of all dermatologic associations. With a membership of more than 20,800 physicians worldwide, the AAD is committed to advancing the diagnosis and medical, surgical, and cosmetic treatment of the skin, hair, and nails; advocating high standards in clinical practice, education and research in dermatology; and supporting and enhancing patient care because skin, hair, and nail conditions can have a serious impact on your health and well-being. For more information, contact the AAD at (888) 462-DERM (3376) or aad.org. Follow @AADskin on Facebook, TikTok, Pinterest and YouTube and @AADskin1 on Instagram. SOURCE American Academy of Dermatology