Here's a 12-year-old notice from the US FDA: Kava-Containing Dietary Supplements May Be Associated with Severe Liver Injury

The advisory does not mention "Happy Camper," though I understand it contains kava-kava (and other ingredients including caffeine). Lots of things can affect the liver. If I were to start on Happy Camper, I'm sure my doctor would watch my liver levels (blood tests) even more closely. Several years of being on Depakote pushed my liver to the limit.