Slide show: Poison ivy and other summer skin irritants

Tinea versicolor is a common fungal infection that causes patches of discolored skin. Tinea versicolor is most common in warm, humid weather. The patches — which can be white, brown, red or gray-black — might be mildly itchy and are often more noticeable after sun exposure. In adults and adolescents, the patches usually develop on the back, chest or arms. In children, tinea versicolor usually affects the face.

Treatments include over-the-counter antifungal creams, lotions or shampoos. Skin color might remain uneven for months, however, and the infection might return — especially in warm, humid weather.