Effects of a Placebo Probiotic on Gut Health and General Well-being in Individuals With Mild Gastrointestinal Symptoms

Condition(s) studied

Investigational drug(s) / intervention(s)

Placebo probiotic: Three-week consumption of placebo probiotic capsules passed off as being actual probiotics

Open-Label Placebo probiotic: Participants of the Control group will be switched to this condition after three weeks and receive placebo probiotic capsules for the following three-weeks of no intervention. Specifically, they will be honestly informed that the capsules are inert placebos.

Control-no treatment: For the first three weeks, the Control group will not be exposed to any intervention.

Study summary

The present study is aimed at exploring whether positive expectations of receiving a three-week treatment with a probiotic supplement (in fact a placebo) improve symptoms of gastrointestinal distress and promote physical and emotional well-being in healthy individuals with mild gastrointestinal symptoms. At first, a comparison is planned between (1) a classic deceptive placebo manipulation (Deceptive Placebo group, DP), and (2) a control condition (Control group, C), in which no placebo substance will be administered. After the three-week waiting list, the Control group will be invited to take the placebo probiotic pills in an "open-label" fashion (Open Label Placebo, OLP). Specifically, participants will be informed that the pills are inert placebos. An exploratory analysis will help to clarify whether the OLP paradigm leads to significant effects, based on a within-group (C- OLP) and between-group comparison (DP-OLP).

Eligibility

Primary outcome measure(s)

• Change from Baseline in the Gastrointestinal Symptom Rating Scale (GSRS) total score at 3 weeks. — Baseline and 3 weeks

Trial sites (1)

More Catholic University of the Sacred Heart trials in Italy

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