I used to be the same way. While I generally scoff at "natural"-sounding cures, tea tree oil (sometimes called melaleuca oil) shampoos have literally cured my problem. I don't know the mechanics of it, but it works extremely well. If you feel like trying it, make sure you get one that is really strong smelling (not a bad thing, the smell is pleasant). I use Paul Mitchell, but others have worked for me too...just not the really cheap ones that barely smell like it.