A recent study by Richard Harris presented at the American Pain Society’s meeting of 18 patients with fibromyalgia showed different brain mechanisms for true and sham acupuncture. It appears that placebo response in sham acupuncture can be differntiated from the true acupuncture response by measuring binding properties of the mu opioid receptor in the brain. This study further confirms the fact that one of the most important mechanisms of action of acupuncture is through the endogenous opioid system and that it is different from the mechanism of the placebo effect.
