Kava is a very potent herb normally, however the kavalactones do break down over time. Also, the normal dose is usually between 5-15 grams or more. The kava supplements in gelcaps are usually worthless. Your best bet is to get whole kava root, the fresher the better. Several online vendors sell good dried kava as well. Kava works as GABA receptor agonist much like benzos. St Johns wort can be used to enhance its effects. Many in the S.Pacific also extract it into alcohol, which also combines its effects. The root of the kava plant are not normally very toxic to the liver, however the arial parts such as the leaves, stems, etc contain pipermethystine which has been shown to cause liver damage. These parts of the plant are not traditionally used, but may be present in supplements. Kava is personally one of my favorite herbs, but I would never buy it in a tablet or gelcap form.