It doesn't last long for most folks - maybe 15 minutes tops when you're completely out of it - but you have zero sense of time so those 15 minutes can feel like years subjectively. Not everyone gets the walkabout thing (or "Puppet Syndrome") on it but it's pretty common and probably the biggest risk of Salvia use. Another commonly told tale around these parts is of a certain member who walked into a fire on Salvia. Fortunately only a sore foot resulted from it but I'm guessing it could have been far more serious if there hadn't have been people around to deal with the situation.
Don't get me wrong, I don't wish to scaremonger, but on Salvia you can certainly move around despite not realising you are doing so. The trip itself can be pretty terrifying for many (most even) but the puppet thing is the biggest reason I don't use it very often cos it really is kinda scary what you can do without realising it. Not saying you actually will go walkies through a window cos it obviously doesn't happen often - if it ever has - but it's a real possibility worth considering.
Salvia effects people very differently - some have very deep and dislocating experiences on low doses, some just giggle like a loon, some are dragged through the pits of hell for a subjective eternity, some find alien bliss, some feel nothing. It's very strange stuff indeed. Personally I would recommend a sitter for anyone using it for the first time (or at high doses) especially. Better to be safe than sorry. Of course everything will probably be fine, but a sitter is not such a bad idea with Salvia.
