Effects of Two Natural Medicine Formulations on Irritable Bowel Syndrome Symptoms: A Pilot Study

Objective: The study objective was to assess the effects and tolerability of two novel natural medicine formulations in improving bowel habit and abdominal symptoms in patients with irritable bowel syndrome (IBS). The DA-IBS formula was designed to treat diarrhea-predominant and alternating bowel habit IBS, and the C-IBS formula was designed to treat constipation-predominant IBS.

Design: This was a two arm, open-label, uncontrolled pilot study.

Settings/location: Subjects were recruited from the greater Lismore area (NSW, Australia) in 2001.

Subjects: The study included 31 patients who fulfilled the Rome II criteria for IBS. Twenty-one (21) patients were classified as suffering from diarrhea-predominant or alternating bowel habit IBS and 10 patients were classified with constipation-predominant IBS.

Interventions: The DA-IBS formula consisted of a mixture of dried, powdered bilberry fruit, slippery elm bark, agrimony aerial parts, and cinnamon quills. The C-IBS formula consisted of a mixture of dried powdered slippery elm bark, lactulose, oat bran, and licorice root. The aim of each formula was to normalize stool frequency and stool consistency.

Results: Ingestion of the DA-IBS formula was associated with a small, but significant increase in bowel movement frequency (p = 0.027). Subjects in the DA-IBS group also experienced reductions in straining (p = 0.004), abdominal pain (p = 0.006), bloating (p < 0.0001), flatulence (p = 0.0001), and global IBS symptoms (p = 0.002) during the treatment phase of the trial. Subjects in the C-IBS group experienced a 20% increase in bowel movement frequency (p = 0.016) and significant reductions in straining (p < 0.0001), abdominal pain (p = 0.032), bloating (p = 0.034), and global IBS symptom severity (p = 0.0005), as well as improvements in stool consistency (p < 0.0001). Both formulas were well-tolerated.

Conclusions: The DA-IBS formula was not effective in improving bowel habit in individuals with diarrhea-predominant or alternating bowel habit IBS, although it did significantly improve a number of IBS symptoms. The C-IBS formula significantly improved both bowel habit and IBS symptoms in patients with constipation-predominant IBS. Further research is warranted on C-IBS, as a potentially useful therapeutic formula.