There is something of an ethical conundrum I think about prescribing—or accepting—harmless placebo treatments for benign psychosomatic illnesses. On the one hand they can help some with mental alleviation. On the other hand, there are several causes for concern.
(1) Expensive placebos have been found to be more effective than cheap ones. Is it ethical to lie about that fact to the patient?
(2) Since placebos do not effect the cause of the illness, they cannot cure it. So if there is some psychological problem which is manifesting itself through some sort of psychosomatic symptom, it will not be cured by the placebo. The symptom may recede for awhile, but it will almost certainly return, so long as whatever problem is the root cause has not been dealt with. This is part of the subject of the above paper. Of course, it is also true that we do suggest palliative therapies for illnesses for which we have no other effective treatments, but at least those therapies do not involve lying to the patient. And if the palliative is given by a competent doctor, he or she will at least be able to know if there is a possible cure. If the placebo is given (as it typically is) by a quack, there is no assurance that any notice will be taken of a possible underlying cause.
(3) Typically placebos are surrounded by a lot of mystical nonsense, e.g., about auras or chi or water memory or crystal healing or whatever. Insofar as the person suggesting the treatment is pushing this sort of woo, it will also tend to mislead the patient about the effectiveness of these nonexistent powers. If they believe that chi can help them with their back pain, they may well decide that it could help them with a more serious illness as well. That is, the mendacity involved with suggesting placebo palliatives for benign psychosomatic illnesses can bleed over into less benign cases.
So I think it all has to be done very carefully. I am not absolutely opposed to a doctor who prescribes a sugar pill for something that he believes is nonsensical and non treatable. At least one can accept the sugar pill without accepting a lot of woo. (And so long as he doesn’t charge some exorbitant amount for the sugar pill, or claim that it can do anything more than alleviate some symptoms). But in general it seems to me that placebos should be avoided.