In "Optimal Wellness", Dr. Ralph Golan states "This condition is thought to be caused by a yeast, Pityrosporum ovale. It may also be related to deficiencies of vitamins A and B, as well as lack of essential fatty acids. food allergies can also be a factor."
For treatment, he recommends eating a whole-foods diet with more fresh fruits and vegetables. Also, identify and avoid allergy-triggering foods. For supplements, he recommends:
vitamin A up to 50,000 IU daily
vitamin B complex up to 50 mg. daily
vitamin B-6 up to 100 mg. daily
PABA up to 500 mg. daily
flaxseed oil 1 or 2 teaspoons daily
borage oil 3 capsules daily
For external application, try a topical cream made with vitamin B-6 (pyridozine) as the active ingredient.