Open Administration of Placebos Greatly Increases Effectiveness

In postoperative pain following the extraction of the third molar (Levine et al., 1981; Levine and Gordon, 1984), a hidden intravenous injection of 6–8 mg morphine corresponded to an open intravenous injection of saline solution in full view of the patient (placebo). In other words, telling the patient that a painkiller was being injected (with …

4.1.3 Expectations of improvement may lead to analgesia

Expectation plays an essential role in placebo analgesia. Modulation of pain perception by placebos depends on expectation, as shown in many studies (Kirsch, 1999; Price et al., 1999, 2008). Montgomery and Kirsch conducted one of the first studies in which expected pain levels were manipulated and directly measured (Montgomery and Kirsch, 1997). They used a …