Tinea versicolor is sometimes called pityriasis versicolor. Its
caused by a yeast (a type of fungus) called Pityrosporum ovale.
This yeast is normally found on skin. But it causes problems
when it overgrows. This often happens in warm, humid climates.
Pink, scaly patches develop on the upper back, upper arms,
chest, and neck. These patches may itch, and eventually turn
lighter or darker than the surrounding skin. If you get a tan,
the condition becomes more noticeable. Your doctor can often
diagnose the condition just by appearance alone. Your doctor may
also confirm it from a skin scraping. He or she will examine the
skin scraping under a microscope to look for yeast forms typical
of tinea versicolor. Your doctor may prescribe an antifungal
shampoo, cream, or lotion. They commonly contain selenium
sulfide, ketoconazole, or pyrithione zinc. These are effective
treatments for tinea versicolor. Using one of them early helps
prevent the infection from spreading. But even with treatment
the condition often return