I took Kava Root extract from Natrol for anxiety, i personally noticed a calming effect. I forget the exact dosage you're supposed to take, so you should go to a site like www.mothernature.com and do some reseach on it. Supposedly too large a dose of it over an extended period of time can cause negative effects on your skin, but if you stay under those large dosages i think it's a useful product.
There has been recent medical releases that Kava Kava could lead to liver damage/failure, just saw a warning in my universities medical center as well :O