Abstract
INTRODUCTION: In disorders of gut-brain interaction including functional dyspepsia and irritable bowel syndrome, clinical focus has shifted from pathophysiological criteria to symptoms. METHODS: A single-arm, low-intervention clinical trial into the effectiveness and tolerability of Menthacarin, a peppermint oil/caraway oil combination, was performed. A total of 126 patients with abdominal pain/cramps or a sensation of being bloated without organic cause received 1 capsule Menthacarin twice a day for 8 weeks. Assessments included abdominal symptoms, stool parameters, and quality of life. RESULTS: During treatment, all assessed abdominal symptoms showed significant (p < 0.001), clinically meaningful improvements, with standardized effect sizes of 0.83-1.05 for change from baseline. The number of days/week with symptom impact or incomplete spontaneous bowel movements almost halved, while days/week with normal stool consistency increased (all p < 0.001). Health-related quality of life significantly improved (p < 0.001) and Menthacarin was well tolerated. CONCLUSION: The study demonstrates patient-relevant improvement in gastrointestinal symptoms during treatment with Menthacarin while underlining its favorable tolerability profile.