Taking these medicines in the forms they are found in nature is a horrible idea. Most of the plants they come from are poisonous because the therapeutic index of most of the drugs here are low, meaning the line between medicine and poison is very fine. Purifying the ingredient and allowing tight control of the dosage is the reason any of these are able to be used safely. Please don't go around eating bits of foxglove or belladonna.

As you've seen, modern medicine is not shy about taking ingredients found in nature when they actually have a useful purpose in medicine, and enabling them to be actually used safely instead of taking some random unknown dosage of a potentially deadly drug and hoping for the best.

Except for fixing vitamin and mineral deficiencies, supplements are ineffective at best and dangerous at worst. They're in desperate need of better regulation in the United States. They scam tons of people and get away with ridiculous claims like fighting dementia based on no evidence that would be totally illegal for any actual pharmaceutical company to claim, all while selling bottles of stuff with "proprietary formulas" or claiming to have plants that aren't even in there when independent researchers look at them. All totally legal by the way, no requirement for ingredients listed on a supplement to reflect reality. Stay away if you value your health or your money. Not saying pharmaceutical companies are always shining beacons of beneficence here, obviously I have many problems with them as well, but they at least have some sort of regulated evidence base for the most part.