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Bowel Regimen Recommendations

For Patients With a Functioning Gastrointestinal Tract

Pharmacologic Classes

  • Miralax – Osmotic laxative
  • Sennokot – Stimulant laxative
  • Milk of Magnesia – Osmotic laxative
  • Bisacodyl Suppository – Stimulant laxative
  • Lactulose – Osmotic laxative

Initial Regimen (At Admission)

  • Start:
  • Sennokot 2 tablets BID
  • Miralax 17 g daily

Escalation Based on Time Without Bowel Movement

After 48 Hours

  • Normal Renal Function:

  • Add Milk of Magnesia 15 mL PO TID

  • Impaired Renal Function:

  • Add Lactulose 20 g PO TID

After 72 Hours

  • Normal Renal Function:
  • Increase Milk of Magnesia to 30 mL PO TID

  • Add Bisacodyl Suppository 10 mg PR ×1

  • Impaired Renal Function:

  • Add Bisacodyl Suppository 10 mg PR ×1

After 96 Hours

  • Add SMOG Enema 120 mL PR ×1
  • Consider abdominal imaging (KUB)

Monitoring: Red Flags for Ileus or Obstruction

If constipation is accompanied by any of the following symptoms, obtain a KUB to assess for ileus or obstruction:

  • Abdominal distention, discomfort, or firmness
  • Decreased or absent flatus
  • Increased belching or hiccups
  • Nausea or vomiting

Bowel Regimen for Non-Functioning Gastrointestinal Tract

Use this section if an ileus is present on clinical exam or imaging.

Initial Management

  • Place NG tube to low wall suction
  • Make patient NPO
  • Initiate IV fluids
  • Monitor electrolytes as needed
  • Continue per rectal bowel regimen
  • Encourage ambulation (if appropriate)
  • Repeat KUB PRN to monitor gas pattern
  • Discontinue or minimize:
  • Opioids
  • Anticholinergics
  • Dopamine agonists
  • Anti-serotonergics

Advanced Pharmacologic Interventions

Ogilvie’s Syndrome (Confirmed on Imaging)

  • Neostigmine
  • Can only be given on 10N
  • Use caution in patients with anastomosis

Postoperative Ileus or Opioid-Induced Constipation

Oral Naloxone

  • Initial dose: 2 mg PO TID
  • Max dose: 4 mg PO TID
  • Max duration: 48 hours
  • Monitor for opioid reversal, especially in liver disease

Methylnaltrexone

  • Dose: 12 mg SQ ×1
  • May repeat after 24 hours if no resolution
  • Use only if:
  • Imaging confirms no obstruction
  • Oral naloxone has failed
  • Must discuss with attending before ordering
  • Use caution in patients with an anastomosis

Management of Diarrhea

Initial Steps

  • Stop all bowel regimen agents
  • Monitor electrolytes

If C. difficile Negative

  • Imodium: 4 mg q6h PRN

  • Fiber supplementation:

  • Without feeding tube:

    • Psyllium: 2 caps daily (max 5 caps QID)

  • With feeding tube:

    • Nutrisource Fiber: 1 packet daily (max 6 packets/day; order under tube feeds)

  • Titrate dose and frequency as needed

References

  1. Yang A, Lam T, Jierjian E, et al. An Evaluation of docusate monotherapy and the prevention of opioid-induced constipation after surgery. J Pain Palliat Care Pharmacother. 2022; 36(1):18–23.
  2. Gathers K, Fawad K, Petros K. Evaluation of methylnaltrexone bromide for the treatment of postoperative ileus. Crit Care Med. 2013;41(12):929.
  3. Chamie K, Golla V, Lenis AT, et al. Peripherally Acting μ-Opioid Receptor Antagonists in the Management of Postoperative Ileus: a Clinical Review. J Gastrointest Surg. 2020. https://doi.org/10.1007/s11605-020-04671-x
  4. Valle RG, Godoy FL. Neostigmine for acute colonic pseudo-obstruction: a meta-analysis. Ann Med Surg (Lond). 2014;3(3):60–64.
  5. Dudi-Venkata NN, Kroon HM, Bedrikovetski S, et al. Impact of STIMUlant and osmotic LAXatives (STIMULAX trial) on gastrointestinal recovery after colorectal surgery: randomized clinical trial. Br J Surg. 2021 Jul 23;108(7):797–803.
  6. Beavers J, Orton L, Atchison L, et al. The Efficacy and Safety of Methylnaltrexone for the Treatment of Postoperative Ileus. Am Surg. 2022; 88(3):409–413.
  7. Gibson CM, Pass SE. Enteral naloxone for the treatment of opioid-induced constipation in the medical intensive care unit. J Crit Care. 2014; 29(5):803–807.
  8. Merchan C, Altshuler D, Papadopoulos J. Methylnaltrexone Versus Naloxone for Opioid-Induced Constipation in the Medical Intensive Care Unit. Ann Pharmacother. 51(3):203–208.
  9. Liu M, Wittbrodt E. Low-dose oral naloxone reverses opioid-induced constipation and analgesia. J Pain Symptom Manage. 2002; 23(1):48–553.

Reviewed November 2024 By

  • Caroline Banes, DNP, APRN, ACNP-BC
  • Jennifer Beavers, PharmD, BCPS
  • Jennifer Emerson, PharmD
  • Bethany Evans, MSN, ACNP-BC
  • Chelsea Tasaka, PharmD, BCCCP
  • Caroline Jackson, PharmD