Individual differences |
Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |
- Main article: Placebo effect
Originally, a placebo was a substance that a well-meaning doctor would give to a patient, telling him that it was a powerful drug (e.g., a painkiller), when in fact it was nothing more than a sugar pill. Thus, Hooper's medical dictionary of 1811 says placebo is "an epithet given to any medicine adapted more to please than benefit the patient." The subsequent reduction of the patient's symptoms was attributed to the patient's faith in his doctor and hence his belief in the drug. (This category, particularly before the first Medicines Act was passed, may merge into fake medicines.)
Placebos as morale-boostersEdit
Hooper’s (1811) Quincy’s Lexicon-Medicum defines placebo as "an epithet given to any medicine adapted more to please than benefit the patient".
In the practice of medicine it had been long understood that, as Ambroise Paré (1510–1590) had expressed it, the physician’s duty was to "cure occasionally, relieve often, console always" ("Guérir quelquefois, soulager souvent, consoler toujours").
According to Jewson, eighteenth century English medicine was gradually moving away from the patient having a considerable interaction with the physician -- and, through this consultative relationship, having an equal influence on the construction of the physician’s therapeutic approach -- and it was gradually moving towards that of the patient being the recipient of a far more standard form of intervention that was determined by the prevailing opinions of the medical profession of the day.
Jewson characterizes this as parallel to the changes that were taking place in the manner in which medical knowledge was being produced; namely, a transition all the way from "bedside medicine", through "hospital medicine", to "laboratory medicine". For more on the effect of the development of various types of medical technology see Medical sign#Increased reliance on signs.
From this point of view, the last vestiges of the "consoling" approach to treatment are to be found in the administration -- often without any sort of adequate history being taken, or any sort of appropriate physical examination being made -- of the morale-boosting and pleasing remedies, such as the "sugar pill", electuary or pharmaceutical syrup; all of which had no known pharmacodynamic action.
Those doctors who provided their patients with these sorts of morale-boosting therapies (which, whilst having no pharmacologically active ingredients, provided reassurance and comfort) did so either to reassure their patients whilst the vis medicatrix naturæ (i.e., "the healing power of nature") performed its normalizing task of restoring them to health, or to gratify their patients’ need for an active treatment.
Some statements about placebos in scientific articles are:
- Cooper (1823, p.259): "[When applying] the compound decoction of the sarsaparilla ... [in cases of] irritable ulcer, ... some think it placebo; others have a very high opinion of its efficacy ... [when it is used] after the use of mercury, it diminishes the irritability of the constitution, and soon soothes the system into peace" (emphasis added).
- Shapiro (1968, p.656): "[This use of the term "placebo" is a form of] positioning ... Introduction of the word placebo to describe a class of treatments not previously specified was an important development in the history of methodology and medicine."
- Handfield-Jones (1953): "some patients are so unintelligent, neurotic, or inadequate as to be incurable, and life is made easier for them by placebo".
- Platt (1947, p.307): "the frequency with which placebos are used varies inversely with the combined intellligence of the doctor and his patient".
- Steele (1891, pp 277-278)"To argue with a man, and especially with a woman, that there is little the matter with them might be thought injudicious, and to advise them to return at a more convenient occasion requires more time and resolution than writing out a prescription or administering a placebo."
- But Shapiro (1968, p.679): "If a placebo is prescribed by a physician because it is thought that it will help the patient, then it is a specific [remedy] and therefore not a placebo [at all]."
- An editorial in the British Medical Journal of 19 January 1952 (p.150): "But it is a fallacy to suppose that an inactive medicine can do no harm. If prescribed in a perfunctory way for a patient needing explanation and reassurance it may increase faith in his disease rather than in the remedy, and a doctor who gives a placebo in the wrong spirit may harm the patient."
- Pepper (1945, p.411): "There may be a time when during the carrying out of diagnostic tests it is undesirable to give potent medicine lest it interfere with the tests and yet the patient must be encouraged by treatment. ... there is a certain amount of skill in the choice and administration of a placebo. In the first place, it must be nothing more than what the name implies a medicine without any pharmacologic action whatever. Even a mild sedative is not a true placebo. Secondly, its name must be unknown to even the most inveterate patient who knows most drugs by name and is always quick to read the prescription. If the medicines named are familiar, the type of patient who needs a placebo will promptly exclaim that this or that drug had been tried and "had not helped me" or "had upset my stomach". It is well if the drug have a Latin and polysyllabic name; it is wise if it be prescribed with some assurance and emphasis for psychotherapeutic effect. The older physicians each had his favorite placeboic prescriptions -- one chose Tincture of Condurango, another the Fluidextract [sic] of Cimicifuga nigra. Certainly this latter by its Latin name might be expected to have more supratentorial action than if one merely wrote for the Black Cohosh, and Condurango would be more efficacious than sugar of milk." Pepper's assertion that a placebo "must be nothing more than what the name implies" -- namely that it must be "a medicine without any pharmacologic action whatever" -- in order for it to be called a placebo, is most significant.
- Findley (1953), p.1826 & p.1824: "[If the placebo is not] used as an instrument of deception, but as a technique for cementing the emotional bond which must attach doctor to patient if any form of treatment is to be really successful… [it was] the most important weapon the physician has ... [specifically because] in proportion as this [doctor-patient] bond is firm, the [patient's] need for drugs will likely diminish."
- Leslie (1954, p.854): "Because medicine has been so concerned with its scientific growth too little attention has been paid to advancing the art of medicine, to which therapy with placebos belongs, and consequently knowledge of the use of placebos has not progressed significantly."
- Carruthers, Hoffman, Melmon & Nierenberg (2000, p.1268): "In clinical practice, where a majority of patient visits are for conditions that cannot be explained on a pathophysiologic basis of for which no specific treatment is available, it is essential that physicians understand the concepts and principles of placebos and placebo effects and, when appropriate, use them correctly".
A "placebo" as "something useless"Edit
Useless decoctions, drugs, treatments, remedies, and procedures are given the pejorative label placebo.
The second edition of Motherby’s (1785) New Medical Dictionary defines "placebo" as "a common place method or medicine" (not "a common place method of medicine" as often misquoted.)
Because this usage does not appear in English (or in any English, French, German, Italian, or Portuguese dictionary) before Motherby’s 1785 edition, Shapiro (1968, pp.656-657) is certain that this pejorative use of placebo was coined by Motherby. That Samuel Johnson's 1755 Dictionary of the English Language has no entry for placebo (or for placebo-singer or singer of placebo, see Placebo (at funeral)), strongly supports Shapiro's contention.
Examples of placebo effectEdit
In 1938, Diehl, Baker and Cowan reported the results of a study that they had conducted over a two year period into the efficacy of injected vaccines in prevention of colds. Whilst their experimental group showed a significant reduction in the number of colds per person per year, the placebo control group reported the same magnitude of reduction as the vaccinated group. This finding was significant, because they also found that their observed level of reduction in the number of colds per person per year matched that of other "uncontrolled studies"; which, given the demonstrated level of placebo responses, meant that "there is no evidence in this study… that vaccines reduce the complications of colds… in a cold-susceptiible group".
By 1948, the term placebo effect was so widely established that an Egyptian physician could write to The Lancet, reporting that "The success achieved in 83% of cases cannot by any means be ascribed to suggestion or to a placebo effect."
In 1949, Wolf conducted a series of investigations into the "measurable "drug effects" that are not attributable to the chemical properties of the agents administered". Wolf contrasting what he called drug effects with what he called placebo effects.
He noted the extent to which the "[observed] "placebo" actions depended for their force on the conviction of the patient that this or that effect would result". He drew attention to the impressive frequency and magnitude of these placebo actions and placebo effects and how they could mimic, mask, potentiate, or prevent beneficial responses to the active drugs. He also stressed that all of these placebo actions and placebo effects, "which [modified] the pharmacologic action of drugs or [endowed] inert agents with potency" were associated with real and substantial physiological changes; and, therefore, they were not imaginary. His study also revealed that the action of a drug could be nullified or, even, reversed in the presence of emotional states such as anger, hostility or resentment.
He also observed that "these effects [were] at times more potent than the pharmacologic action customarily attributed to the [active] agent". and spoke of the well-established understanding "that the mechanisms of the body are capable of reacting not only to direct physical and chemical stimulation but also to symbolic stimuli, words and events which have somehow acquired special meaning for the individual", in the hope that, "in the future drugs will be assessed not only with reference to their pharmacologic action but also to the other [psychodynamic] forces at play and to the circumstances surrounding their administration".
<ref>tags exist, but no
<references/>tag was found