I've too heard that tea tree oil works. I think it was actually from DH. He's totally not gay or geeky even, but he, for a while, was really into essential oils and how they help the body, etc. I know...kinda weird for a guy. He also got really into yoga and all kinds of "girly" things. ANYWAY, I think he did mention that for ance before. I've never tried it myself. I think he has the actual oil somewhere around. I should give it a try. I'm sure the shampoo is much cheaper than the oil though.
