I was wondering myself if tea tree oil was an issue for me. I used Giovanni Tea Tree shampoo a few times, I noticed it gave me flakes. As soon as my scalp dried, flakes everywhere. It was bad. The one time I had good results with it I mixed it 50/50 with conditioner and scrubbed like hell. No flakes. But I am happier with creamier cleansers or cowashing now. My scalp feels less dry.