Kava kava has caused liver problems in the past because ignorant or greedy people would manufacture it using other parts of the plant besides the root. The root itself is completely safe.
I have used kava kava myself and I have had no problems, unfortunately, I had no relief from my anxiety either. I forget where I read this, but I read that there over 70 different types of metabolisms. So what is great for one person may not be anything fine for another. What's the saying? One mans trash is another mans treasure.
The stuff tastes like dirt, but its not so bad. If it helped I would have kept on taking it. I would just be careful who I ordered it from. It's legal to order it for personal consumption in Canada.
In case of Psychosis, call 666.