Despite its sun protective abilities, sunscreens containing oxybenzone can occasionally cause contact allergies and photo-allergic contact dermatitis. This means that, when exposed to sunlight, susceptible persons may develop an itchy rash on their exposed skin. Among common sunscreen chemicals, oxybenzone is most likely to be associated with allergic reactions triggered by sun exposure. In a study of 82 patients with photoallergic contact dermatitis, over one quarter showed photoallergic reactions to oxybenzone.