Opium tincture has anti-propulsive effects in patients with chronic diarrhea: a randomized, placebo-controlled, and cross-over trial.

Objective: Chronic diarrhea affects approximately 5% of the population. Opioids inhibit gastrointestinal motility, and opium tincture has shown anti-propulsive effects in healthy, but no controlled studies of its clinical efficacy exist. We aimed to investigate the anti-propulsive and central nervous system (CNS) effects of opium tincture in patients with chronic diarrhea.
Materials and Methods: The study was a randomized, double-blinded, placebo-controlled, cross-over trial in subjects with chronic diarrhea refractory to standard treatment. Participants received opium tincture or placebo during two intervention periods, each lasting seven days. Bowel movements were recorded daily, and gastrointestinal transit time was investigated with the wireless motility capsule system. Gastrointestinal symptoms, health-related quality of life, and CNS effects (pupil size, reaction time, memory, and general cognition) were also investigated, along with signs of addiction.
Results: Eleven subjects (mean age: 45 ± 17 years, 46% males) with a median of 4.7 daily bowel movements were included. The number of daily bowel movements was reduced during opium tincture treatment to 2.3 ( p  = 0.045), but not placebo (3.0, p  = 0.09). Opium tincture prolonged the colonic transit time compared to placebo (17 h vs. 12 h, p  < 0.001). In both treatment arms, there were no changes in self-reported gastrointestinal symptoms, health-related quality of life, or CNS effects, and no indication of addiction was present.
Conclusion: Opium tincture induced anti-propulsive effects in patients with chronic diarrhea refractory to standard treatment. This indicates that opium tincture is a relevant treatment strategy for selected patients with chronic diarrhea. Moreover, no evidence of opioid-induced sedation or addiction was found. Trial Registration Number: NCT05690321 (registered 2023-01-10).