Control of Radiation-Induced Diarrhea with a Psyllium Bulking Agent

Testing Control of Radiation-Induced Diarrhea with a Psyllium Bulking Agent: A Pilot Study

Pelvic radiation therapy is notorious for triggering diarrhea—an uncomfortable side effect that can disrupt patients’ daily lives and treatment plans. In this pilot study, Murphy and colleagues recruited 60 cancer patients receiving pelvic radiation (at least 4,000 cGy over four weeks) and randomized them to either take psyllium (as Metamucil) or not. The goal was to determine whether this soluble fiber supplement could help control radiation-induced diarrhea, using daily patient-reported diaries and the custom Murphy Diarrhea Scale to assess outcomes.

The findings revealed a meaningful impact: psyllium intake significantly reduced the incidence of diarrhea in comparison to the control group. Moreover, it significantly improved severity, with less intense symptoms reported by those taking the fiber supplement.

Psyllium also demonstrated a favorable trend in reducing reliance on anti-diarrheal medications, though this did not quite reach statistical significance.

In summary, this study suggests that daily use of psyllium during pelvic radiation can both decrease how often diarrhea occurs and ease its severity—and may even lower the need for extra medications. It highlights a promising, simple, and low-cost supportive care option for patients managing the side effects of radiation therapy.

References

Murphy J, Stacey D, Crook J, Thompson B, Panetta D. Testing control of radiation-induced diarrhea with a psyllium bulking agent: a pilot study. Can Oncol Nurs J. 2000;10(3):96‐100

By Dr. Sydney Moffat, ND and Dr. Gurdev Parmar, ND, FABNO(USA)