'Love Hormone' May Mediate Placebo Effect - MedPage Today

Intranasal oxytocin, sometimes called the "love hormone," intensified the painkilling effect of placebo in a clinical study, suggesting a physical basis for the placebo effect, researchers said.Among 75 healthy young men exposed to painful heat stimuli on their forearms in the randomized, double-blind study, ratings of a placebo cream's analgesic effect were greater after the participants received active intranasal oxytocin than when they snorted a saline solution, with a difference of 5.76 points out of 60 (95% CI 0.59-10.93, P=0.03), according to Ulrike Bingel, MD, of the University of Duisberg-Essen in Germany, and colleagues."To our knowledge, our study provides the first experimental evidence that placebo responses can be pharmacologically enhanced by the application of intranasal oxytocin," they wrote in a research letter appearing in the Oct. 23/30 issue of the Journal of the American Medical Association.The experiment was designed in such a way as to exclude the possibility that oxytocin itself affected pain sensitivity, the researchers said."We hypothesize that oxytocin might have increased the believability of the instructions by the study physician," Bingel and colleagues wrote. Also, they suggested, the hormone may have reduced anxiety and stress, which in turn could have increased the placebo response.They had hypothesized that oxytocin might have such an effect because earlier research had associated its release with psychological traits such as t...
Source: Psychology of Pain - Category: Psychiatrists and Psychologists Source Type: blogs