weird combo
why would you mix these two?
i asume you take the mdma first and then (on the peak?) smoke salvia.
my idea is that the salvia will not give full effect because for salvia you need a very quiet, calm set and setting (dark room, sitting in a couch or in bed)...
and this is quite hard on mdma.
also, there are studies that show that salvia works on the dreaming mechanism.
personally, i experience salvia better when tired.
if you are going to do this combo, go low dose on mdma