Placebos: A review of the placebo response

Placebos have been a component of healing since the beginning. Whether cons ciously or unconsciously given, they are largely responsible for the succes s of medicine before randomized trials. Yet, even in this era of "evidence- based medicine," placebos remain enigmatic, and elicit mixed attitudes from divers disciplines. However, our ignorance is not total. There are a few f acts to cling to and old myths to dispel. The effect of placebos seems to e ncompass such disparate elements as anxiety, conditioning, expectation, the healer's persona, and the attachment of meaning to illness. Placebos may o bscure as well as illuminate the truth about treatment effectiveness. Moreo ver, it is easy to confuse their effect with the natural progression of the disease being treated. Those engaged in treatment trials must recognize an d manage the reality of placebos rather than attempt to eliminate or dispar age them. Factors that might influence the placebo effect such as age, gend er, and social circumstances need prospective study. Meanwhile doctors, thr ough honest and compassionate interactions with patients, should strive to maximize their treatments' benefits. This implies confident reassurance and the provision of some meaning to the person's symptoms. (C) 2000 by Am. Co ll. of Gastroenterology.