For those who haven't had much luck with dandruff shampoos, it might be psoriasis or excema, which will not respond to dandruff shampoos. If it's excema, it could be a symptom of an allergy. I had it for years until I cut dairy from my diet. It comes back whenever I eat dairy for 2 days in a row or more. Head and Shoulders has a shampoo that uses a different chemical(selenium sulfide) from the rest of their line, called "intensive treatment". I use this every other day, alternating with Trader Joe's Tea Tree Tingle shampoo, which has tea tree oil and some other herbs that are supposed to be good for a dry scalp.