Utilizing placebos to leverage effects of cognitive-behavioral therapy in patients with depression

Patients with depression often experience difficulties with completing homework assignments during cognitive-behavioral therapy (CBT). In the present study, we investigated the effects of a specific placebo which aimed at improving the practice of a daily relaxation exercise during a four-week outpatient program.

A total of 126 patients diagnosed with major depressive disorder were randomly assigned to one of three groups: 'Coping with Depression' course, 'Coping with Depression' course with additional daily placebo treatment, and waiting-list group. The placebo (sunflower oil) was introduced as a natural medicine to help the patients focus on their inner strengths and to mobilize their bodies' natural healing powers. The placebo was taken orally before the daily relaxation exercise.

The placebo improved homework quantity and quality (both p < .001). The placebo group practiced more often and experienced greater relaxation effects than the no-placebo group. Additionally, the placebo group showed a greater reduction of depression symptoms (p < .001).

The primary limitation of the study is the lack of a psychophysiological measure of relaxation.

Placebos can be used to leverage CBT effects in patients with depression.