Yes the Intesinal Formula #1 does contain Senna and Cascara and I know and have heard not take this over 7 days. However Dr. Schulze advises that this is a correction formula to take as long as needed to get your bowels corrected this seems to be the only product that works. I have trid several different fibers and cleanses oxygen and arise and shine. Not sure who to belive don't need to make a lazy colon any more lazy then it is either.