Pain: The science and culture of why we hurt
The full quote/excerpt
… the more we learn about the placebo effect, the more ammunition it gives to the pharmaceutical companies. They now have evidence that round white pills are less effective than a colored tablet with corners, and that certain colors have more powerful associations. Red suggests power, green and blue are associated with calm, and the most promising pill is a capsule with lots of colored beads inside. (Witch doctors with feather anklets may have the right idea.) Also, a patient is more likely to respond to an injected placebo than to a pill, because we have learned that injections are serious medicine. And an intravenous placebo, with a nice little hanging bag attached, is the best of all.
Shortened version of the quote
A patient is more likely to respond to an injected placebo than to a pill, because we have learned that injections are serious medicine.