osmoprep-how long until it kicks in?

When I used mine they kicked in at bedtime...no sleep for me that night. The scope I had this past time with the visocol tabs they had me start much earlier in the day this way I was able to sleep. Eventually what comes out will be prettymuch bile. The frequency at which you go depends on your bowel habits with out the prep meds (I always had C) as well as meals you have eaten yesterday and the amount you ate.