Your doubting Dr. Schultz? Have you ever read in depth about his products?
Yes, I have. This is why I would not touch most of his products. In my opinion his products are based on old school herbology, which relies heavily on herbs that have since been proven to pose problems. For example, he uses a lot of stimulant laxatives. Stimulant laxatives such as senna, cascara sagrada, rhubarb root, cape aloe and curacao aloe can cause electrolyte imbalances and will cause a laxative dependence in as little as two weeks of use. The berberine herbs (goldenseal, Oregon grape root, barberry, etc.) kill the intestinal flora, damage the intestinal lining and depletes potassium leading to high blood pressure. He uses horsetail grass (shavegrass), which is a strong vasoconstrictor. This makes it dangerous for people with congestive heart failure, arteriosclerosis, Raynaud's disease or syndrome, diabetes or that are also taking non-steroidal anti-inflammatory drugs. There are higher silica sources that are much safer. He uses lobelia in some formulas and ginger in others. These should not be taken together. Since people may take more than one formula this poses a potential danger. I have also seen blue cohosh in one formula, which is another toxic herb not to fooled with. Then there is the fact that he combined uva ursi with other herbs, which is actually the most common formulating mistake I see made by various formulators. As I said earlier, too often "herbalists" will read somewhere that a particular herb does something in particular and throws it in the mix without bothering to research the safety nor the chemistry to know how it will interact with other herbs. Uva ursi is not to be used for more than 4 days in a row without a break since it can irritate the kidneys. More importantly though uva ursi is very high in tannins, which bind the active constituents of the other herbs it is combined with thereby decreasing their effectiveness. This not only applies to uva ursi, but also to other high tannin herbs such as white oak bark, green tea, etc.
I notice he also likes to use hot peppers in a lot of the formulas. This can be a problem for people sensitive to nightshades and salicylates. And hot peppers are not as good for circulation as they have been made out to be. Capsaicin, the active component in these peppers, mainly dilates superficial blood vessels and is short in duration. A better choice would have been prickly ash bark, which is more effective in dilating the deeper, primary blood vessels and has a longer lasting effect than hot peppers. And no issues with nightshade or salicylate sensitivities.
There are others, but these are the main ones. This is also a great example of why herbalists and formulators need to actually research herbal chemistry, safety and interactions before simply throwing a bunch of herbs together and calling it a formula.