All in the mind…. the placebo effect

LanceArmstrong

Placebo – Drug of Champions?

Could infamous cycling champion, Lance Armstrong, have done so well if his ‘drug of choice’ had been a placebo?  I pose the question because it may not be as ludicrous as it sounds according to research by Italian neuroscientist Dr Fabrizio Benedetti. Although with hindsight, believing Armstrong was so successful without assistance seems just as ludicrous.

Most people have probably heard of ‘the placebo effect’. This is a term I seem to be hearing with more regularity and recently I have begun to wonder if it has become just another fashionable, catchy saying; likely misunderstood and misapplied but used nevertheless because it sounds edgy and knowledgeable.

There also seems to have been a cultural change in attitude towards the framing of placebos. This may be due in large part to increasing distrust of prescription medications and the appeal of the idea of non-intrusive healing through ‘positive thinking’ or of ‘mind over matter’; especially when the terminally ill and their loved ones are desperately looking for a cure where conventional treatments no longer give any hope.  Guess et al (2002) also note a shift in the bio-medical research field and among medical practitioners, describing the placebo as, ‘transformed in a few short years from a sham in medical practice and a control agent in clinical trials to a therapeutic ally’, (p.1).

To most lay people I think ‘the placebo effect’ is commonly understood in reference to patients taking a ‘pretend medication’ (placebo) but when believing it to be real attest to a physical response to the ‘medication’ – which may be either positive or adverse. This is how I would have explained the placebo effect if asked but I was by no means sure I understood the phrase properly either. Are people really misinformed when they think the placebo effect points to an ability of the mind to enhance the body’s ability to overcome physical ills? It is certainly an appealing concept and one which can seem more reasonable when we are forever being told how little we truly understand the workings (or unmapped potential) of the human brain.

And so sensing I was on shaky ground in my own understanding of the placebo effect I decided to make it the topic of a couple of blog-posts and I discovered there are a number of interesting perspectives to discuss.

So here goes…. a brief history on the origins of the placebo…. (and its effect).

The term ‘placebo’ comes from the Latin verb ‘placare’ which means ‘to please’ (as opposed to ‘nocebo’ which means ‘to harm’). Although ‘placebo’ started to be used in English during the 13th century, it wasn’t part of medical terminology until the late 18th century. A medical dictionary from 1811 defined the term as ‘any medicine adapted more to please than benefit the patient’ which reflects the practice of doctors of the time to give some patients placebos in the form of bread or starch pills because they had little confidence in the efficacy of their ‘real’ range of medications. Doctors would also prescribe ‘sub therapeutic doses’ of ‘pharmacologically active drugs’ (Edward 2005, p.1023) in order to satisfy those patients who were simply looking for the process of treatment and possibly to protect their authoritative standing.

Generally, a placebo is an inert substance with no inherent pharmacological activity, and looking, smelling and tasting like the real drug being used. An ‘active placebo’ may be used which is one possessing its own inherent effects but which don’t apply to the condition for which it is being prescribed.  A placebo may also be a procedure rather than drugs or medication. This can be quite extreme extending to placebo surgery where a patient is anaesthetised and ‘superficial procedures’ including skin incision are performed without surgery being undertaken (Rajagopal 2006). I have been wondering if the previously mentioned ‘placebo surgery’ is a treatment or a component of clinical trials. Either use is somewhat hard to fathom and points to much of the current debate surrounding the ethics of using placebos through deception, although technically participants in clinical trials must be made aware that they may receive a placebo rather than the active drug or real procedure.

The phrase ‘the placebo effect’ has been attributed to American anaesthetist Henry K. Beecher in his work, ‘the powerful placebo’ (1955), when he reported that, on average, a third of his patients with a range of medical complaints improved when taking placebos. Rajagopal (2006) claims this then led to the use of placebos in the establishment of randomized control trials (RCT) where ‘active drugs’ are tested against placebos rather than no treatment which Edwards (2005) suggests, ‘implicitly assumes that the placebo itself exerts an effect’ although not of a pharmacological nature (p.1023).

In the next blog-post I will identify current opposing (as well as overlapping) views of researchers about the application of placebos, including a case study, and return to make sense of the question first posed by this post: Could Lance Armstrong have done so well if his ‘drug of choice’ had been a placebo?

References:

Edwards, M 2005, ‘Placebo’, The Lancet, vol. 365, pp 1023.

Guess, HA, Kleinman, A, Kusek, JW, Engel, LW 2002, The Science of the Placebo, BMJ Books, London.

Rajagopal, S 2006, ‘The placebo effect’, The Psychiatrist, vol. 30, pp 185-188.

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