Definition

A placebo is a medical term for a drug that has no active ingredient. Biologically, it doesn't do anything, but the patient might mistakenly believe it is a powerful medicine. In fact, in bygone eras, some people who [Page 671]took snake oil and other medically useless substances did get better, partly because they believed that these substances would cure them. The phrase placebo effect refers to a person's response to a substance only as the result of the expectation of such a response. The response is called a placebo effect when the substance is known not to induce any response, but a consistent response is found. Because of the placebo effect, people may experience or perceive the effects of medication, such as pain relief or ...