xZapx
I feel a need to chime in here - I cannot vouch for the Nature's Way version of the formula but here's my side of things.
I've been taking the Lower Bowel TONIC - 2 capsules, 3 times a day as Dr. Christopher Recommends. I just took the recommended month off after taking it for over *6 months* and I can assure you I have better bowel function than when I started. Cascara Sagrada stimulates and helps rebuild the peristaltic muscles. Yes, the small amount of Turkey Rhubarb is laxative in nature, but it makes up a tiny portion of each capsule and adds to the formula's synergy. I had more need for it during the formula before I ever started taking than I do now, however I plan to keep taking it for the duration of the 9-12 months that will continue to treat the original problems at a deeper level and resolve them.
When eating a plant based, beneficial diet as recommended Potassium will be in much more abundance than any small amount that the herbs could effect. I wonder how much Potassium is in the other plants in the formula itself. I can't speak to the effects of killing flora but I certainly don't have any of the symptoms of that. Eating beneficial RAW fruits and vegetables helps replenish the flora, and every bowel movement removes millions of them.
I agree that we need to be respectful of the herbs we use for ourselves. When harvesting, MH has talked about not over harvesting. Dr. Christopher always spoke about this as well. Organic (or regular cultivated) Goldenseal (from reputable sources) is still available and used by many individuals, including myself so as to not contribute to the problem of over harvesting of wild growth. It is arguable that wild harvested herbs will be more potent, and someday when I have a place to do so, I will encourage their growth and responsibly harvest what I need for myself.
The bigger problem with goldenseal is the many people using it with one or no other herbs, in large quantities. Then it can have some effects that you speak of, and in those cases there are other herbs which may even be more appropriate anyway.