It's white flaky scaly stuff that itches and flakes off in mass quantities and looks like dandruff. Nasty stuff, I had a horrible case of it about a year ago and it was a bite to get rid of. A dermatologist can give you steroid creams for it or sometimes something like Head and Shoulders shampoo can help. Good luck, it's icky stuff! Mine tends to come out in time of stress.....

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