In Brief: Placebos are not all alike
Placebos are not all alike
Can one placebo be better than another? That's the conclusion suggested by a study in which acupuncture was compared to the antidepressant amitriptyline and to placebo versions of both in the treatment of repetitive strain injury.
Nearly 300 people with arm pain were given two weeks of placebo treatments; half of them received sham acupuncture and the others a sugar pill. Then half in each of those groups continued to take a placebo while the rest were given genuine treatment: acupuncture for four weeks or the drug for six weeks (it often takes that long to work). All patients were told about the most common side effects of the treatment they were taking.
Beginning at the third week, fake acupuncture was more effective than the placebo pill in reducing subjective pain (although not in improving grip strength). A higher proportion of the acupuncture patients believed they were receiving active treatment (75% versus 48%), but that apparently did not affect the result. At the end of treatment, believers had improved no more than non-believers.