Valerian Root and negative side effects

Valerian root worked wonderfully for me--when I would wake up in the night i would take two capsules and go back to sleep within an hour. Even when I would take it at 4 a.m. and get up at 6, I would awake refreshed and have no "drug hangover." However, I believe it built up in my system, and it then caused negative side effects. My heart began pounding at night, my stomach was nervous and even seemed to quiver sometimes on the left, and i had pain on the right that I initially thought was my liver. The day before I quit taking it, I was itchy all over. That was when I realized that Valerian root was probably the source of all my negative symptoms. After not taking it for two days I began to quit feeling nervous and sick and itchy. I guess the lesson is that a person should only use this herbal supplement occasionally and in small doses.