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Herbal Placebos

The seven-year period within which member states must implement the EU directive on herbal medicine ends next month. In the UK, the government last week announced that herbalists will now be regulated by the Health Professionals Council (HPC). The HPC is the body that currently supervises a number of health professions including paramedics and physiotherapists. The effect of the decision has been to trigger concerns, particularly from medical professionals, that the move will confer legitimacy on treatments with no proven benefit. But if the government is going to permit herbal medicine, then there are in fact grounds to make it as plausibly medical as possible.

While the debate between proponents and opponents of herbal medicine is heated and at times resembles that between theists and atheists, there is little serious doubt that herbalism is not medicine. The directive doesn’t even really pretend that it is. The emphasis is instead on (1) lack of harm and (2) plausible efficacy “on the basis of long-standing use and experience.” If this is the case, then it appears that any efficacy can only be the result of the placebo effect. Bennett Foddy has blogged here recently on how powerful this can be. Research indicates that it can have an as strong impact on wellbeing as powerful painkillers, including cancelling out the effect of traditional medicine.

If this really is the effect of herbal medicine, then why not embrace and promote it? Having a body that regulates other health professionals also regulating herbalists seems likely to confer an impression of medical respectability. As such, this should enhance the placebo effects. Treatment using herbs costs a fraction of that for conventional medicine. Furthermore, while there are understandable concerns that individuals approaching herbalists might not seek effective medical treatments that are available, regulation by a medical body would appear to be a way of minimising this. The HPC could require herbalists to ensure that those that they treat are also informed of the medical treatments that may be available. The only real downside is that the benefits of the placebo effect will not be available to those sceptical of the claims of herbalists.

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9 Comment on this post

  1. "…The only real downside is that the benefits of the placebo effect will not be available to those sceptical of the claims of herbalists."

    Is that really the only downside? The benefits of the placebo effect require subtantial patient ignorance about their medical treatment. To be sure, it seems a plausible conjecture that the benefits of the placebo effect are inconsistent with genuine informed consent.

    Do we want to promote patient understanding and research of their medical conditions and treatment options, such that patients might actually know enough about the mechanisms of action for each treatment option for them to make informed treatment choices? Do we really want to promote a treatment whose benefits require patient apathy/ignorance about medicine generally and their own treatments and treatment options particularly?

  2. Unfortunately the situation is a bit more complicated than that, with herbals. Unlike like homeopathy, which is pure placebo, herbal remedies sometimes do have physiological effects. The problem is that those are not well understood, standardized, and regulated.

  3. The "complication" of the situation that you point out (in comment/response #2 above) is of course well known and only exacerbates the problem.

    Placebo effects of herbals require patient ignorance, lack of patient awareness of treatment, treatment mechanisms of action, and general education/information about treatments and informed consent. (Do you we really want to encourage and foster an ignorant and uninformed/uneducated/badly educated patient population?)

    The herbals are well understood by botanists. Mainstream medical sciences are also well familiar with plant biology, from which so many tried and true medicines derive. The difference between Taxol and Taxotere, for instance, on the one hand, and the sort of herbs your local herbalist or alternative medicine source/practitioner is most likely to provide, on the other hand, is that the former have gone through rigorous testing and clinical trials, and the latter are either often if not usually not carefully tested or already known to be contraindicated with the most effective treatments. Everyone oncologist I know pleads with their patients not to take any herbals or other alternative medicine products, especially while they are taking carefully tested pharmaceuticals – which is always their first choice lines of treatments by definition for reasons of tested and demonstrated effectiveness/safety.

    There are very good reasons (sketched above) not to take or prescribe herbal placebos to the extent to which they function as placebos. There are also very good reasons (sketched above) not to take or prescribe herbal placebos to the extent to which they function as medicines; if there were, the relevant experts or the corporations they work for would quickly patent them, carefully test them, and carefully produce them, in which cases the mainstream medical establishment would no longer call them "herbals" or categorize them under "alternative medicine". Taxol could have qualified as an "herbal" as some point, though no oncologist I know considers Taxol or Taxotere "herbals" (roughly for the reasons sketched above).

  4. I'm not convinced that placebo effects require as much patient ignorance as is being assumed here. In triple-blind experiment even those administering the pills are not allowed to know whether they are placebos or "the real thing". Presumably this is because there is evidence that a placebo effect can be transmitted simply through body language. Or take coffee: these days I am no longer "ignorant" of the fact that it takes a good half hour for the caffeine to be absorbed into the blood stream, but this does not prevent the stimulant effect (presumably due to placebo) taking effect pretty immediately. Even the most knowledgable of us are not as "rational" as we sometimes like to think we are, and the case of then placebo may shed light on why this has been selected for: it allow us to enjoy placebo effects while still retaining accurate information. Essentially one suspends disbelief in certain cases.

    In any case as long as we don't want to ban these products altogether it seems reasonable to want to regulate them. Far from "conferring legitimacy", the implication seems to be that a potential for harm has been identified, which the market alone cannot be trusted to prevent.

  5. Hey, I am all for regulation as regards harm/lack of harm. What I do not find plausible here is the alleged justification for regulation as regards placebo benefits (along with the use of placebos as/in medical treatments). This alleged implausibility does not deny any facts about placebos, which of course are quite fascinating.

    The examples listed in the first paragraph of the response/comment above simply describe possible placebo effects. Basing medical treatments on placebos and their alleged effects is not the time to conduct experiments to learn about the mind/brain. "Enjoying placebo effects while still retaining accurate information [about all relevant matters that a patient should ideally know and understand about their treatment oiptions]" will not last for long, and may never occur for many people in various circumstances. People in need of serious medical treatment for serious medical illnesses (a huge consumer base for herbals and other alternative medicines) are not the appropriate population either to experiment on with placebos or to try to treat with placebos, for the reasons sketched two comments up, in my opinion

  6. David I was not suggesting that the purpose of regulation could ever be to "conduct experimens to learn about the mind/brain" or that we should be seeking to experiment on populations of seriously ill people or "treat them with placebos". My point was rather that what we already know now, or at least are beginning to learn, about placebos cast doubt on your claim that "placebo effects…require patient ignorance". By contrast I tend to agree that the justification proposed by Paul is insufficient.

  7. Apart from out apparent agreement that the justification proposed by Paul is insufficient, we appear empirically to disagree about the kinds and degrees of ignorance of placebos required for their effects (and thereby their use in testing treatments as well as administration of treatments). Apart from your personal anecdotes, can you refer to the studies that support your views? From what I know, administration of a placebo, by simple definition, essence, or meaning, requires patient ignorance (of whether patients are receiving placebos or actual treatments that the placebos epistemically mimick without containing the alleged active ingredient in/component of the actual treatment). Roughly, the less deception, the smaller the placebo effect and the smaller the number of patients in placebo control groups who experience a placebo effect. Similarly, the more deception, the greater the placebo effect and the higher the number of patients in placebo control groups who experience a placebo effect. If you like, I can provide extensive references for each of my beliefs/claims about placebos. Which ones specifically do you call into question?

    Tell people after knee surgery, for instance, that the pills you are about to give them contain nothing but sugar and salt even though those pills have the same shape and color of other pills that contain powerful narcotic pain killers, and the patients will not experience a placebo effect. If you disagree, can you please explain how and in what ways? The same goes, I would argue, for all treatments with placebo effects. One of the serious problems with lending any credibility to treatments with herbal placebos is that although placebo effects do not work for many very serious medical conditions, herbalists and a great many of the alternative medicine practitioners who prescribe/recommend them do not restrict their herbal prescriptions and recommendations to the less serious medical conditions for which placebo effects occur.

  8. Just to be clear (and perhaps more simple and concise), given Paul's apparent concession that herbalism is not medicine, it seems to me that placebo effects from herbal "medicines" require false beliefs – and/or ignorance – about medicine and herbs. A bit more particularly, herbal placebos seem to require ignorance and false beliefs about herbal medicine and (ignorance and/or false beliefs about) the alleged mechanisms by which herbs produce their (alleged) effects.

  9. I don't have specific studies to hand, David, but Ben Goldacre's Bad Science is a good source of references on the placebo effect in general, as I expect you are aware.

    You ask how a patient who knows he/she is being given a placebo could still experience the effect. While the personal anecdotes I have described obviously do not themselves constitute scientific evidence that this could be the case, I believe they do shed light on possible mechanisms. An analogy can be drawn with advertising. Many adverts work by creating some kind of "feel-good" factor around the product being advertised. Few people seriously believe that the "nice" things being associated with the product in the advert actually have anything to do with the product (you can also drive through beautiful scenery in a second-hand skoda), but the effect still operates at a subconcious level. It is therefore not implausible to me that some (obviously reduced) placebo-like effect could accrue even when the patient knows it is a placebo, simply because the patient has a mental association between the placebo and (in your example) the painkiller. Whether this still constitutes "administration of a placebo" is indeed a matter of definition.

    I certainly *don't* disagree with the idea that the intensity of the placebo effect is positively correlated with the degree of deception/ignorance, I'm just not convinced that it actually falls to zero when there is no actually deception/ignorance.

    As Chris MacDonald has pointed out, herbal treatments can have actual chemical effects, so they are not pure placebos. Apart from these comments, however, I have no particular dispute with your general conclusions about the dangers inherent in lending credibility to herbal treatments (although we may still differ on the extent to which regulating them actually does this).

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