I've heard that when you just start smoking salvia, you get a reverse tolerence and it takes less and less to get you fucked up each time, and I actually found that to be true my second. third, fourth, etc times... It started taking a little more after about 7 times smoking it; but still putting .01 grams on top of weed gives me a nice buzz... I'd say I've only smoked it.. 9 times or so