When some people take Kava Kava root and see there results, I try and find out which blood type they are. This, for now, is unproved, but appears to be for some people blood type changes the way certain herbs work in their bodies. A few people that I know that take Kava root tend to be a blood type O and it works great! While others who are type A it does not work as well for them. Valerian root seems to work best for type A people. I will need to look further into this in the future, but think it would be an interesting study.
There are other plants that help anxiety, too. Skullcap, lemon balm, hops, and chamomile seem to be the top contenders. In a life as stressful as the modern age, turning to natural sources for help with little side effects would be great!
Of course, with all “medications” (herbs, supplement, and drugs are all in the category together) you sh9uld contact your physician to check to and cross reactions.