It sounds like
seborrheic dermatitis, which is an inflammatory version of dandruff. I have it in my eyebrows -- it's white and flaky, with no redness until recently, and it started off in one part of one eyebrow, and then it spread. Now recently it has spread to my entire eyebrow. I've tried a lot of things. Using Nizoral shampoo once a day seems to help a little. I also take the following supplements: evening primrose oil, multivitamins, cod liver oil, and sometimes, probiotics.