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Bowel Regimen

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Author: Joseph R. Sweigart 


Oral Agents (from above)

Stool softeners: affect stool only, no affect on colonic activity

  • Docusate: detergent (micelles), softens/liquefies stool
  • Psyllium: soluble fiber, bulkens and softens stool
    • Bulkens diarrhea, softens constipation; ideal for regulation in IBS

Stimulants: increase colonic motility, no affect on stool; best if scheduled

  • Bisacodyl: neurogenic stimulant and contact irritant, increases colonic activity
  • Sennosides: neurogenic stimulant, increases colonic activity
    • Dose can be up-titrated fairly safely; good for opiate-induced ileus

Osmotics: pull fluid into lumen; most often used PRN

  • Gentle but reliable (trucks)
    • Magnesium hydroxide (MoM): common OTC; avoid if ESRD
    • Polyethylene glycol (PEG): synthetic non-soluble fiber
  • Non-gentle and potentially a bit messy (plows)
    • Magnesium citrate: rapid-acting; avoid if ESRD
  • Aggressive (bulldozers)
    • High-volume PEG (golytely): non-digestible
    • Lactulose: digestible by colonic bacteria, can cause painful gas
    • Sodium polystyrene (kayexalate): theoretically absorbs potassium


Suppositories (pills from below)

Effects localized to rectum, useful only when soft stool in vault

  • Docusate: detergent, placement causes irritation
  • Bisacodyl: stimulant, placement causes irritation


Enemas (liquids from below)

Affect rectum and above depending on volume, useful when hard or no stool in vault

  • Low volume: reach into rectum and sigmoid colon
    • Sodium phosphate (fleets); avoid if ESRD
    • Mineral oil
  • High volume: reach above sigmoid colon
    • Tap water: safe, fairly gentle, risk of hyponatremia
    • Soap suds: safe, lower risk hyponatremia, more cumbersome to administer


Ideal prophylactic regimen

Useful if opiates, anticholinergics, elderly, fluid restricted

Something schedule (hold if diarrhea): sennosides, bisacodyl

  • Optional docusate (possibly less effective to contract against liquid)

Something PRN: MoM, PEG


Ideal treatment regimen

  • Useful if already constipated (no BM in >48 hrs) or impacted (rocks in rectum)
  • Aggressive schedule (until BM): sennosides or bisacodyl –AND- MoM or PEG daily
  • Daily enemas: tap water or soap suds daily if no BM in >24 hrs
  • High-volume PEG (bulldozer) if no BM in >48 hrs despite above