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Condition

Bowel Cleansing

Bowel cleansing is the process of emptying the colon before a colonoscopy, surgery, or imaging test, usually with a clear liquid diet and a large volume of prep solution that can leave the gut dehydrated and its microbiome disrupted. Little research on supplements for it has been reviewed here so far, so there are no trial findings to report yet. Electrolytes, probiotics, and simethicone are the most discussed options, but that reflects their proposed roles rather than results.

Supplements studied
1
Graded outcomes
0
Trials
2
People studied
569

Evidence by supplement

  • Strong
  • Moderate
  • Limited
  • Very limited

1 supplement

Senna: outcomes studied for Bowel Cleansing
GradeOutcomeEffectSizeStudiesPeopleStudies list
Intestinal MotilityImproves (the measure goes up)8 studies569 people

The Bowel Cleansing (Colonoscopy Preparation) Supportive Care protocol

2 primary supplements · 5 supporting supplements

  • Probiotics20–50 billion CFU daily starting immediately after procedure and continuing for 2–4 weeks
  • ElectrolytesClear electrolyte beverages or oral rehydration solution as tolerated during and after prep

See the full protocol

Shop the evidence-backed picks

Fullscript collectionGut and digestion: evidence-graded picksOpen on Fullscript

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Studies cited

8 studies from PubMed

  1. Senna vs polyethylene glycol for mechanical preparation the evening before elective colonic or rectal resection: a multicenter controlled trial. French Association for Surgical ResearchArch Surg · PMID 10323423
  2. The bowel cleansing for colonoscopy. A randomized trial comparing three methodsAnn Ital Chir · PMID 17147088
  3. Half doses of PEG-ES and senna vs. high-dose senna for bowel cleansing before colonoscopy: a randomized, investigator-blinded trialAm J Gastroenterol · PMID 19844199
  4. Comparative study of two bowel preparation regimens for colonoscopy: senna tablets vs sodium phosphate solutionWorld J Gastroenterol · PMID 17006995
  5. Comparison of the effect of drugs upon some commonly used measures of bowel transit timeBr J Clin Pharmacol · PMID 728318
  6. A volunteer model for the comparison of laxatives in opioid-related constipationJ Pain Symptom Manage · PMID 8935140
  7. The use of senna with docusate for postoperative constipation after pelvic reconstructive surgery: a randomized, double-blind, placebo-controlled trialAm J Obstet Gynecol · PMID 20207340
  8. Standardized senna in the management of constipation in the puerperium: A clinical trialS Afr Med J · PMID 6996138