FTFY. The amount of psychoactive pharmaceutical drugs cooked up by big companies is immense. It seems to be a slow process for natural substances, because there's no money in that and it can't really be patented to maximize profits.
https://www.asyousow.org/environmental-health/toxic-enforcem...
And many pharmaceuticals start from natural substances that had to be refined. There's nothing humans don't understand about refining and purifying, we've done it for a very, very long time. It's a solved problem. Greed is not.
There are plenty of reputable manufacturers who wouldn't think of adulterating medicine or misleading their customers, but all it takes is a couple sleazy Chinese vendors on Amazon to spoil the entire apple-barrel.
For example, my potassium iodide specifically instructs the user to consume it orally, which is dangerously incorrect. I believe that if they put the correct instructions on the bottle, the product would be so efficacious that it'd demand removal from the market.