I drank Kalm with Kava concentrate on and off for about two weeks (with a little instant root here and there) and didn't really get to the kava epiphany state until the end of that period. It was really like someone flipped a switch for me. I've heard reports from people that it's taken them longer than 2 weeks to build up sensitivity. Once it happens, though, you'll know it and it'll be freaking awesome.