It always amazes me how people can speak with confidence about the placebo effect. Just what kind of phenomenon is it? Is it actually a manisfestion of self-organisation, of the biological ability to self-heal? If so, isn’t it something we should try to understand in order to maximise it?
Instead, placebo is frequently presented as “nothing”. The assumption is that a “placebo response” is not a “real” or “effective” response, and when used in randomised controlled trials, it is equated with doing nothing. In other words, if a treatment cannot demonstrate a statistically greater effect than a “placebo” it is considered to be “ineffective”. But is that true? Irving Kirsch has shown very clearly that “placebo” and “doing nothing” are far from the same, so it is illogical to argue that a treatment which produces a strong “placebo” response is “ineffective”.
Now here’s another interesting angle on the debate. A paper published in the Annals of Medicine about use of placebos in clinical trials points out that less than 10% of trials give any information about the make-up or content of the “placebo” used in the trial. Is this important? Well, they argue, yes, because sometimes the ingredients in the “placebo” produce a negative effect, and sometimes a positive one, but if we don’t know what was actually used, how can we make sense of the results?
This conclusion is fascinating –
“there isn’t anything actually known to be physiologically inert. On top of that, there are no regulations about what goes into placebos, and what is in them is often determined by the makers of the drug being studied, who have a vested interest in the outcome. And there has been no expectation that placebos’ composition be disclosed. At least then readers of the study might make up their own mind about whether the ingredients in the placebo might affect the interpretation of the study.”
Heroes Not Zombies 
Good point Bob. The placebo effect is a variable effect, which is often referred to in the media as though it were a constant. It will amongst other things vary from condition to condition, and clinician to clinician. Presumably it can also vary from near 0 to near 100%.
We should look to quantify the placebo effect at least. So for example in this trial, on this condition, the effect of the medicine was x%, and the placebo effect was y%.
This would be a start in helping us to understand what is going on a little better.
Who said that placebos were things that had no physiological function.Who said that?Where is this person?
Where is the science in this? If this worked why are there so many problems with prescription drugs?
——The problem that we will be left with, whether or not placebos are fully understood and or standardised, is inertia. For example, a randomised double blind trial could be conducted with a homeopathic remedy like Arsenicum Album, against a so called placebo. The trial could reveal that after a week of patients receiving one of either of the two prescriptions, 30% of individuals given the so called placebo reported that their symptoms had eased, compared with only 19% of those given homeopathy. If in a matter of a few days after the trial was concluded, the homeopathic arm could have then risen to 60% and the placebo arm remained the same, it would not be reported in the results, as the trial had already been concluded! Perhaps, a stage of clinical inertia would have passed and the remedy (Arsenicum) had now taken effect, but as the research had been concluded, no one would know that this had happened! Any researcher wishing to discredit homeopathy therefore, has an easy job on their hands. Unfortunately, we now live in a world where: “It only works well if it works quickly.” I submit that ‘therapeutic inertia’ would be a very interesting area of study in conjunction with the placebo and nocebo response. Colin I. H. Perry.
Mike Dixon’s ‘Placebo Effect’ is a very interesting book on the subject of placebo. Haven’t got time to condense them here but check it out.
“It only works well if it works quickly” – I suspect, and I actually read somewhere about the long term follow ups on a conventional medication – I think it was asthma – which only gave improvement for the first 2 months, but 6 months later the patients were almost no better off than they were in the beginning. While indeed I would think that with homeopathic treatment the picture will be reverse – and with placebo – one needs to find out! So what can be campaigned for is that clinical trials had the period covered by the trial extended to at least 1 year for all sorts of drugs and trials. After all, it is long-term effects that are important to the patients!