His argument was thus - the illusion of intervention delivers a clinical benefit: patients who think they have been given a treatment often behave as if they have been given a treatment. The more invasive or involved the illusion is, the bigger the impact of the phoney treatment. An injection of saline is more effective than a sugar pill, and a surgical scar is more effective than an injection.
The rub comes that the placebo effect requires the person administering the phoney treatment to collude, and not let the patient know that they are being given an inactive treatment.
In the case of the alternative therapies, for which no evidence of impact has been demonstrated, we are given a demonstration of how elaborate successful delivery of the placebo effect can be: in these circumstances it is not just the patients who are being duped - the therapists have also signed up for the illusion. And perhaps this is what it takes for the placebo effect to be its most effective: for the therapist to also think that they are delivering effective treatment.
The current tradition within evidence based medicine is to cancel out the placebo effect, and this is achieved through the use of double-blind studies. We seek to give treatments that have benefit beyond placebo, and reject those that offer nothing more.
So far, I have not told you anything you don't know (perhaps I rarely do). But my friend was arguing that if the placebo effect has a measurable and reliable clinical benefit, are we not beholden as doctors, to exploit all techniques available to us in the name of best clinical outcomes? There are many conditions for which we have no effective (as measured by RCTs) treatments, and in such circumstances, our approach currently is to offer an explanation to our patients, and offer them the best symptom control that we can. My friend would have us behave differently.
And he makes an interesting point: our choice not to take advantage of the placebo effect is compounded by some other aspects of the phenomenon: the fact that we have no understanding of the mechanisms by which the effect is exerted should make it an important line for research, and yet it remains on the fringes of clinical investigation. The reality of the placebo effect in every treatment we use should mean that it should be taught and discussed on medical school courses in great detail. Medicine often treats the placebo effect like an embarrassing relative: we simply pretend it doesn't exist.
And yet it offers us opportunity where our medical sciences have so far failed to deliver, and it perhaps offers us an insight into health and healing, and how to influence them positively. We know that we can exert a positive clinical benefit by doing something as minor as giving a sugar pill, and we know that we can exert bigger impacts by giving more invasive placebos, like intravenous injections of saline, or surgical scars, underneath which there has been no actual surgery.
At the moment, we throw away explanation of this process, simply by saying it is the placebo effect, and giving it no further explanation or enquiry. The fact that it does not conform to our scientific models of enquiry and explanation has meant that we do not give it due consideration. The term 'placebo effect' has become a short hand for the sentiment that we cannot understand or explain this phenomenon, therefore, there is not further reason to mention it.
However, perhaps medicine could open new avenues to whole new forms of treatment by gaining a handle on the mechanisms underlying the placebo effect, and exploiting them to gain greater clinical benefits.
Perhaps if this were to happen, if harnessing the placebo effect were to become an evidence based practice, informed by high quality clinical research, the action of doctors in using it for the benefit of the patient could move from being the action of the deceitful to well-informed clinical intervention.
But until this time, in the context of modern clinical practice, most doctors should be uncomfortable with the idea of engaging in regular and institutionalised deception of their patients.
We know that there are few certainties in medical practice, and the positive movement we have made in the last few decades has been a greater degree of transparency and involvement of our patients in the health choices that directly affect them.
Any move to deceive patients in the name of better health would need to be done with the broad agreement that it is appropriate to do so. It is not the role of doctors to decide the morality of health care by themselves - it is the role of doctors to deliver healthcare that is ethical with reference to the standards of the communities they serve.