Effects of pill-giving on maintenance of placebo response in patients with chronic mild depression

Fifty outpatients with mild, chronic, mood-reactive depression whose mood improved markedly after a 10-day single-blind placebo trial were randomly assigned in a double-blind design either to have their placebo medication discontinued or to have it maintained for an additional 6 weeks. Half of the patients in each condition relapsed within 6 weeks, indicating that pill-taking itself does not influence maintenance of placebo response. Placebo response was more likely to be maintained in patients who were currently married. At the end of 3 months, the overall relapse rate was 58%. The authors raise questions about the utility of the initial 10-day placebo washout in antidepressant clinical trials, and they discuss limits on the generalizability of their findings.