We have some clues but not much real, deep understanding of how general anesthetics work. Process that for a second. They've been in use since at least the ear

We have some clues but not much real, deep understanding of how general anesthetics work. Process that for a second. They've been in use since at least the early 19th century. We have had a bunch of them (though in humans, at least, we pretty much only use 4 or 5 in developed countries these days). We do this every day in surgical suites around the world. People expect to be unconscious during surgery. But we don't really know how they do it. Or take antipsychotics: the companies were looking for antihistamines and noticed psychotic patients got better on some of them. If it works... you keep using it until something better shows up.