the gambling with the drugs, a thousand different answers on the Internet, what is correct?

It is crazy, for every disease and every drug there are many answers. Worse yet, the answers sometimes totally contradict each other. I searched for a particular drug and found dozens of different clues about the side effect. In the end, the drug was thought to trigger the very disease it is supposed to be working against. The side effect was really bad stuff. I called my doctor and he calmed me down and said that this is also about "national pride"! So what is that ??? In fact, some medicines are demonized in one country and the other is "the drug of choice." How does that work?
I hope my doctor knows what he is doing, what can I do but trust?