The publication Efficacy of open-label placebos for premenstrual syndrome: a randomised controlled trial by Dr. Antje Frey Nascimento from the Department of Clinical Psychology and Psychotherapy at the University of Basel was awarded the Steven Karger Prize 2025  in November 2025. The study investigates the effectiveness of openly administered placebos in the treatment of premenstrual syndrome (PMS) and provides groundbreaking insights for clinical practice.

Background and significance of the study:

Premenstrual syndrome (PMS) is a highly prevalent disorder that comes along with substantial psychological and somatic distress and functional impairment. Not only is the condition underexamined and underreported, current treatments show partially limited benefits, are associated with considerable side-effects, and low acceptability. For a variety of physical and mental complaints, there is clear evidence that openly prescribed placebos – open-label placebos- lead to symptom reduction. We conducted the first randomized-controlled trial with an open-label placebo intervention for women affected by PMS and premenstrual dysphoric disorder and examined further the impact of the provision of the treatment rationale for open-label placebos. The results of our study reveal that openly prescribed placebos lead to significant and clinically relevant reductions in PMS symptom intensity and interference. Our findings indicate that the open-label placebo intervention could serve as a viable treatment alternative for women living with PMS. Moreover, our study showed that the provision of the open-label placebo treatment rationale was the crucial component of the intervention and, thus, highlights the need for sound informed consent procedures in clinical practice and the potential that the provision of treatment rationales contains concerning treatment effects.