I think as well as what others have said, an ethical consideration with placebos is that they are treating someone with something that they know doesn’t work. Like, basically, on some level, it’s ethically dubious to make you go to all the effort you outlined, interact with medical staff, receive an actual injection, etc, and deliberately not treat you. That’s why many many trials have “stopping rules”, where if it turns out the treatment is working really well, the placebo group gets it, too.
I think as well as what others have said, an ethical consideration with placebos is that they are treating someone with something that they know doesn’t work. Like, basically, on some level, it’s ethically dubious to make you go to all the effort you outlined, interact with medical staff, receive an actual injection, etc, and deliberately not treat you. That’s why many many trials have “stopping rules”, where if it turns out the treatment is working really well, the placebo group gets it, too.