Perhaps you are thinking of the harmful and addictive effects of todays NON-natural laxatives. Many people, especially elderly, become so dependent on laxatives that their bowels would be unable to function if they stopped.
Such is not the case with the IF#1. Dr. Schulze 's ingredients are all natural, made from nature, not processed and do not contain chemicals. These ingredients are found in nature. They are NON habit forming. You can take a very large amount if you wish (though why you would want to do this is beyond me) and all that will do will give you what I believe her refers to as "jet-propulsion" coming out of your bottom. In other words, the most insane diarrea you ever had.
These herbs do not damage your other organs, in fact, with your colon funcitoning better than ever, that means that THEY can do THEIR jobs better, as your body is able to purge itself of toxins instead of letting them sit in your system and be reabsorbed. Makes the kidney happy, makes the heart happy, etc.
I am wondering where you heard that these herbs were so awful. Have you read Dr. Schulze 's patient handbook ? As long time user of both his intestinal formula, I can tell you that my life has improved dramatically for the better after doing these. My health is better than ever, like when I was a little kid. My body funcitons smoothly and well, and I am not sick or unwell all the time like I used to be.
Hope that helps and good luck with your cleansing!