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The extraordinary power of placebos merits special discussion. Its size and pervasiveness can best be illustrated by quantitative data from experimental studies.2 In 15 different studies involving more than a thousand subjects, placebos satisfactorily relieved on the average 35 Âą 2.2% of subjects. The great power of placebos provides one of the strongest supports for the view, that drugs that are capable of altering subjective responses and symptoms; do so to an important degree through their effect on the reaction component of suffering. Beecher, in studies of severe post-operative pain extending over a number of years, found that 30% or more of these individuals got satisfactory pain relief from a placebo.1 Th is becomes more impressive when one realizes that Lasagna and Beecher found that the average effectiveness of a large dose of morphine 15 mgm/ 70 kg. body weight relieved only 75%. Thus of the average pain relief produced by a large dose of morph ine in treating severe pain nearly half must be attributed to a placebo.3 In another study, evidence was presented that placebos are more effective the greater the stress. This is supported by further observations that placebos are less effective in studies of experimental pain than they are when the pain arises in pathology. They are found to be ten times as effective in relieving pathological pain over experimental. Pathological pain produces more anxiety or stress. Approximately the same high level of 35 % effectiveness was produced whatever the subjective state under examination ; pain of angina (26-38% ), seasickness (58%), cough (40%), common cold (35%), and tension and anxiety (30%) . In a study of 199 patients with headache, 120 got relief from placebos. Hillis in studies of inhibition of the cough reflex obtained an effect with placebos as great as that observed with 0.03 Grams Codeine. OCTOBER,
1964
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Diehl investigated the ability of a vaccine to prevent colds. He found a reduction in the number of yearly colds of 55 % among those given vaccine and 61 % among a control group who received injections of isotonic Sodium Chloride. Besides these beneficial effects, placebos were held responsible for many untoward effects e.g. insomnia and dizziness. The "placebo reactor" still remains to be positively identified. There is a great deal of disagreement about placebo reactors; whether they even exist is disputed . Wolf denies the existence of a " placebo reactor" and considers the placebo effect unpredictable and even variable in the same patient; a fundamental point, for Lasagna feels that reactors should be excluded from double-blind studies. 12 • Prior to the study of Lasagna no previous attempt h ad been made to investigate the distinguishing personality characteristics of the placebo reactor. 10 Lasagna concluded that the reactor is a recognizable type but only with the aid of an intensive interview, plus psychological testing. It was clear that the placebo reactors did not belong to the lunatic fringe of the population, they were neither whiners nor notable incompetents, neither male or female, neither young nor old. Their average intelligence was the same as that of the non reactors. Some of the personality characteristics which differed in the reactor and non reactor were as follows. Reactors on the whole tended to be more expansive, cooperative and uncomplaining, regular church goers, and slightly less educated. They used drugs more frequently e.g. aspirin and cathartics. On psychological testing, reactors were more anxious, more self-centered and preoccupied with internal bodily processes. They are individuals who seem more dependent on outside stimulation than on their own mental processes. Their instinc101