Introduction despite recent passionate doubts about the effectiveness of placebos, is no doubt that there are contextual effects linked to medical interventions: not only the physical heals. As such placebo effect is evident and independent of placebo (understand reduccionistamente as substance or surgical procedure): behind a treatment there are 3000 years of medicine. This may be very obvious, but there are indications that this reality is currently one minor both in research and in clinical praxis role. There is almost universally (in all cultures, in most of diseases or disorders) a clinically significant improvement top margin to do nothing (control group). Wren Collective oftentimes addresses this issue. However, we don’t know what is, do not know set it and know how to use it. The strangest thing is that it does not seem to import us this ignorance: we are against perhaps the cheaper therapeutic agent, available and relatively effective (in terms of the number of treatable symptoms) that is known, and yet mysteriously is ignored. Although used throughout history, from the explosion of scientific advances in modern medicine, it seems that the use of therapeutic factors associated with beliefs has been marginalized.The reasons may be several (escapes to current scientific methodological resources? do lack of interest comercial-empresarial? is an ethical issue (deception)? O have been dropped in prejudice of associate placebo with an obstacle for the advancement of science in clinical trials?), but not applicable here discuss them. In fact, it seems that here just exists today an interest in this topic.

However, in general, would seem that almost nothing is known about placebo. Thus, the objective of this article is trying to reflect on what it is, and in particular to try to see if there is way to benefit us deliberately. Distinguish disease ill concept of placebo: according to Brody, is a change in the health or physical condition of a person attributable to the symbolic impact a certain stimulus (Brody limits to medicine: treatment or treatment situation).

Thus, has shown effective in various types of pain (headaches, sciatica, dysmenorrhoea), immune mechanisms, ulcerative colitis, tardive dyskinesia, congestive heart failure, etc, and ineffective in other pathologies (do OCD, dementia?). Placebo can exercise effect on measures objective (blood pressure, Gastric motility, lung function), even type nocebo (vomiting, sweating, skin rashes). A recent study shows that half of the residents of internal medicine from a U.S. hospital believed that administered placebo could discriminate between real and imaginary or Hays symptoms. The subjects that they respond to placebo have a definite personality: attempts to identify characteristics not only of personality, but demographic u others predicting the response to placebo have been unsuccessful so far. Even individuals tend to vary in time (sometimes significantly) in its response to placebo. In a series of experiments that have become a classic in the field, varying between unpleasant and intolerable intensity shock were administered to a group of volunteers.

Then were given a face cream with the (false) message that was analgesic: some responded to placebo and were able to tolerate discharges that previously were intolerable. The most interesting thing was the second phase: after returning to provide them with cream, this time was made to the subjects believe that is was administered them current when in fact it was not: subjects in this case came to believe that the cream should really have analgesic, so that properties returning to manage the currentone much higher percentage was able to tolerate the unbearable pain of downloads. Among other findings, shows that you people in the first phase they did not respond to placebo, had been trained in producing a perfectly clear answer to the same placebo. Mechanisms proposed three types of beliefs involved in the placebo effect: a) of the patient: expectations (believe they are giving you a leaf of a plant that produces allergy causes really, even if you rub with another innocuous, and vice versa) b) of the clinician: believing that a therapy is effective, you can associate with an index of improvement between 70-90% of cases (of e.