"Fake medical treatment can work amazingly well," writes Rebecca Tuhus-Dubrow. "For a range of ailments, from pain and nausea to depression and Parkinson’s disease, placebos—whether sugar pills, saline injections, or sham surgery—have often produced results that rival those of standard therapies. ... And as evidence of the effect’s power mounts, members of the medical community are increasingly asking an intriguing question: if the placebo effect can help patients, shouldn’t we start putting it to work? In certain ways, placebos are ideal drugs: they typically have no side effects and are essentially free.