Most weight loss treatments have terrible side-effects. GLP-1 is working pretty well as a target now, but all the other ideas didn't turn out so simple after all, and there were a lot of ideas for weight loss drugs
In my opinion orlistat (blocks fat absorption) isn't that bad if you actually follow the suggested low-fat diet. But if you're hoping to counteract a pint of ice cream, it's going to work tooooo well. The Public Relations was a nightmare... never stood a chance. The jokes were too good.
Acarbose blocks starch (and sucrose, to some extent) absorption. Instead of oily poop you get dry smelly gas that hopefully goes down over time. Starch & sucrose is not as big a part of American caloric intake as fat, but it can still help cut some of that out.
(Just sucrose. HFCS has glucose and fructose, which means sucrase doesn't need to work. Not a meaningful difference in most people considering how fast sucrase works, but when you block sucrase...)