The Pharmaceutical Journal Vol 267 No 7177 p814
8 December 2001

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Is there such a thing as a talisman effect?

By John Wilson

One great advantage of being semi-retired but still active professionally is that I can pick and choose what I do. I particularly enjoy being a "flying locum", covering occasional days at a wide variety of pharmacies. Sometimes these days are booked well in advance. Others can best be classed as emergencies, for instance, when a pharmacist is ill. Alternatively, as happened recently, when a previously booked locum failed to arrive, I have to hurry, cavalry-like, to the rescue.

As the locum, and unlike a manager or proprietor, I have no duties other than the immediate professional work. Therefore in the occasional quiet periods I can fit in some professional reading or look around the pharmacy. The goods sold in pharmacies vary greatly, from the health centre pharmacy that has a couple of shelves of over-the-counter medicines and nothing else, to quite large stores with a huge range of goods. A couple of pharmacies in which I worked recently were selling therapeutic magnets. The product looked a little like a wrist watch, and had a magnet that could be placed in four positions. The wearer adjusted the position of the magnet until relief was obtained from a variety of painful conditions.

Magnet therapy has been around for a very long time. There is scientific evidence that magnets do have an effect on living organisms. Some species (probably including humans) are sensitive to magnetic fields. Some migrating birds are known to use the earth’s magnetic field as a navigation aid. However, the scientific evidence for the relief of pain by magnets is, to say the least, scanty.

My spirit of scientific enquiry led me to contact the manufacturers of the "magnetic wrist watches" to ask for any scientific data that they might have. What I received was a batch of "unsolicited testimonials" from "satisfied customers" — not what I would call scientific data at all. This led me to think about the reasons that people use such products, and to wonder if it might be a placebo effect.

The term "placebo" comes from the Latin "to please". In order to obtain a marketing authorisation, a manufacturer has to demonstrate that the new drug is "better than placebo". This is shown by carrying out a clinical trial. However, one of the most worrying aspects of clinical trials, for the manufacturers and for health care professionals, is the magnitude of the "placebo effect" sometimes obtained. In other words, those patients who take tablets containing no active drug often seem to improve during the trial. Nowhere is this effect more dramatic than in the case of psychotropic drugs, particularly antidepressants. Two factors are likely to contribute to the improvement seen in the placebo group: the placebo effect proper, which can arise from the encouragement the patients receive to take the medicine and the knowledge that someone is taking the patient’s condition seriously, and the natural course of the condition, with fluctuating symptom levels.

Meta-analysis

In a delightfully controversial article to which they gave the title "Listening to Prozac but hearing placebo", Kirsch and Sapirstein1 used a meta-analysis to identify the magnitude of the placebo effect. In the 19 placebo-controlled trials of antidepressants that they examined, they found that the placebo response was consistent at about 75 per cent of the drug effect, and the correlation between placebo effect and drug effect was 0.90. These data, they suggest, indicate that nearly all the variation in drug effect size was due to the placebo characteristics of the studies. In addition, the effect size for active medicines that are not considered to be antidepressants was as large as that for those classified as antidepressants. They conclude that, in the trials of antidepressants that they surveyed, approximately 25 per cent of the drug response is due to the administration of an active medicine, 50 per cent is a true placebo effect and the remaining 25 per cent is due to other, non-specific factors. Although the original paper produced the expected vigorous response, such findings need to be taken seriously. After all, the National Health Service spends millions on antidepressant treatment, and if 50 to 75 per cent of the effect is placebo . . .

My thoughts on the possible placebo effect of the magnets led me to contemplate why patients fail to "comply" with their medication. (Perhaps, now that we talk of "concordance" and not "compliance", there is a need for a new verb — "to concord?") Anyway, patients do not take their medicines as directed by the prescriber and this is clearly shown in a recent PJ news feature.2

This news feature claims that between 10 and 20 per cent of the annual prescribing budget is taken up by wasteful prescribing, which it defined as a mixture of prescribing a drug that is not clinically indicated and of unnecessary repeat prescribing. These medicines are then "flushed away", according to the editorial in the same issue.3 (I do hope not. Waste medicines should be incinerated at an appropriate temperature.) However, let us consider this apparent waste a little more carefully.

It is often assumed that patients fail to take their medicine but continue to order repeat prescriptions (thereby amassing stocks that eventually get returned to the pharmacy and placed in the special waste bins) because they want to "please" the doctor. Alternatively, it is because they dare not tell the prescriber that they have stopped taking the drugs. Do we have any real evidence of this? Could there be another, equally rational, explanation?

The placebo effect is now well recognised. I propose that there is a special case of the placebo effect, which I will call the "talisman effect", in which the mere possession of a medicine is in itself therapeutic. A talisman is defined by Encyclopaedia Britannica as "an object bearing a sign or engraved character and thought to act as a charm to avert evil and bring good fortune". Talismans, amulets and the like have an ancient history. Even in our supposedly scientific age, one still sees St Christopher pendants hanging from the internal rear view mirror of cars.

Supposing that a belief in the power of such a talisman actually works, because of some complex placebo effect in the mind of the owner, that so far we have not really investigated? This could extend to medicines. How many asthma patients, for instance, will panic and have an asthma attack if they find that they have left their blue inhaler at home, when the knowledge that it is within reach seems to reduce the number of attacks? I do not think that this effect has ever been investigated. So, the concept of a medicine as a talisman may bring a whole new dimension to pharmacotherapy.

Finally, may I suggest that all pharmacists who carry a salbutamol inhaler in their briefcase or handbag as a talisman to ward off asthma attacks should check the expiry date? I checked mine some time ago and got a surprise. It would seem that the talisman effect is real after all.

References

1. Kirsch I, Sapirstein G. Listening to Prozac but hearing placebo: a meta-analysis of antidepressant medication. Prevention and Treatment 1998; 1:0002a (available at http://journals.apa.org/prevention/volume1/pre0010002a.html).

2. Bellingham C. How pharmacists can help to prevent wastage of prescribed medicines. Pharm J 2001; 267:741–2.

3. Waste not, want not (edit). Pharm J 2001;267:732.

John Wilson is a pharmacist based in Arnold, Nottinghamshire