What are the prokinetics for paralytic ileus?: A comprehensive guide

October 12, 2025 •

3 min read

Paralytic ileus, a temporary cessation of intestinal movement, is a common complication following abdominal surgery and can significantly increase hospital stay. Prokinetic medications are used to help stimulate the gut and restore normal peristalsis, but their effectiveness and safety vary, requiring careful consideration.

Quick Summary

This guide covers the prokinetic medications used for paralytic ileus, detailing their mechanisms, specific applications, side effects, and evidence supporting their use. It also explores non-pharmacological management strategies.

Key Points

Alvimopan is approved for postoperative ileus (POI): This peripherally acting µ-opioid receptor antagonist helps accelerate bowel function recovery after bowel resection in patients using opioids.
Neostigmine is used for acute colonic pseudo-obstruction (ACPO): This acetylcholinesterase inhibitor is particularly effective for Ogilvie's syndrome when conservative measures fail, but it requires careful monitoring for side effects like bradycardia.
Older prokinetics have mixed evidence for ileus: Metoclopramide and erythromycin show inconsistent efficacy for general postoperative ileus and carry risks of serious side effects, such as tardive dyskinesia (metoclopramide) and cardiac issues (erythromycin).
Supportive care is the foundation of management: Primary treatment involves bowel rest, IV fluid/electrolyte management, opioid minimization, and early mobilization, which are critical for resolving paralytic ileus.
Treatment should be multimodal and individualized: Effective management combines targeted prokinetics with supportive care strategies, tailored to the patient's specific cause of ileus and overall clinical picture.
Alternatives include non-pharmacological methods: Early enteral feeding and chewing gum are simple, low-risk interventions that can help stimulate peristalsis and promote recovery.

Understanding Paralytic Ileus and Prokinetic Therapy

Paralytic ileus, or adynamic ileus, is a temporary paralysis of the intestinal muscles, leading to a blockage of the gastrointestinal (GI) tract without a physical obstruction. The condition often arises postoperatively after abdominal surgery, but can also be triggered by severe illness, electrolyte imbalances, certain medications (especially opioids), and infection. Symptoms include abdominal distention, nausea, vomiting, mild pain, and an inability to pass gas or stool.

Prokinetic agents are a class of drugs designed to stimulate GI motility by enhancing coordinated muscle contractions (peristalsis). The goal of prokinetic therapy for paralytic ileus is to reduce the duration of bowel rest, facilitate the return to oral feeding, and decrease hospital length of stay. However, the efficacy and safety profile of these agents differ, and their use requires an understanding of their specific mechanisms.

Key Prokinetic Agents for Paralytic Ileus

Alvimopan (Entereg)

Alvimopan is a peripherally acting µ-opioid receptor antagonist (PAMORA). It is approved for short-term use in hospitals following specific bowel surgeries. It works by inhibiting µ-opioid receptors in the gut, which can be useful in postoperative ileus associated with opioid use.

Neostigmine

Neostigmine is a parasympathomimetic drug primarily used for acute colonic pseudo-obstruction (ACPO or Ogilvie's syndrome) when other treatments are ineffective. It works by increasing acetylcholine to stimulate colonic motility. It is administered intravenously or subcutaneously. Cardiac monitoring may be necessary with intravenous administration due to potential side effects like bradycardia.

Metoclopramide (Reglan)

Metoclopramide is a dopamine antagonist commonly used for gastroparesis. Its effectiveness for general paralytic ileus is limited and inconsistent. It stimulates upper GI motility. Risks include extrapyramidal side effects.

Erythromycin

Erythromycin can act as a motilin agonist at low doses to stimulate GI motility. It is sometimes used off-label for conditions like gastroparesis, but evidence for its use in general paralytic ileus is mixed. Potential side effects include GI upset and cardiac issues.

Comparative Overview of Prokinetic Agents for Ileus


Feature	Alvimopan (Entereg)	Neostigmine	Metoclopramide (Reglan)	Erythromycin
Indication for Ileus	Specifically approved for postoperative ileus (POI) following small or large bowel resection.	Treatment of acute colonic pseudo-obstruction (ACPO) when conservative measures fail.	Use for ileus is limited; better evidence for gastroparesis and feeding intolerance.	Used off-label for gastroparesis or feeding intolerance; mixed evidence for ileus.
Mechanism of Action	Peripherally acting µ-opioid receptor antagonist (PAMORA), blocking opioid effects on the gut.	Acetylcholinesterase inhibitor, increasing acetylcholine to stimulate colonic motility.	Dopamine D2 antagonist and serotonin 5-HT4 agonist, promoting upper GI motility.	Motilin receptor agonist, stimulating gastric and small intestinal contractions.
Efficacy in Ileus	Strong evidence for reducing time to GI recovery in specific surgical patients.	Effective for ACPO, with rapid response observed.	Inconsistent and limited evidence for hastening resolution of general POI.	Mixed evidence for general ileus; may be used for feeding intolerance.
Key Side Effects	Cardiovascular events (not significant with short-term use for POI), pain, dyspepsia.	Abdominal cramps, bradycardia, hypotension, nausea.	Extrapyramidal symptoms, tardive dyskinesia, depression, fatigue.	GI upset (nausea, pain), hearing loss, QT prolongation (cardiac risk).
Route of Administration	Oral (capsules).	Intravenous or subcutaneous.	Oral or parenteral (IV).	Oral or intravenous (IV).

Broader Management Strategies for Paralytic Ileus

Prokinetics are part of a broader approach to managing paralytic ileus, with conservative management as the cornerstone.

Supportive Care: Includes bowel rest, IV fluids and electrolytes, and nasogastric decompression if needed.
Opioid-Sparing Pain Management: Reducing opioid use with NSAIDs or multimodal analgesia is crucial.
Early Mobilization: Encouraging movement helps stimulate bowel function.
Non-Pharmacological Stimulants: Chewing gum may help stimulate bowel function.
Early Enteral Nutrition: Reintroducing food early can help prevent severe ileus.

Conclusion

For paralytic ileus, Alvimopan is effective for postoperative ileus after bowel resection, especially with opioid use. Neostigmine is the preferred treatment for acute colonic pseudo-obstruction unresponsive to conservative care. Metoclopramide and erythromycin are less favored for general postoperative ileus due to limited evidence and significant risks. Effective management combines supportive care, opioid-sparing strategies, early mobilization, and targeted prokinetics. Treatment should be individualized. You can find more information on promotility agents in a review from the Eastern Association for the Surgery of Trauma {Link: EAST https://www.east.org/education-resources/practice-management-guidelines/details/promotility-agents-for-the-treatment-of-ileus-in-adult-surgical-patients}.

Frequently Asked Questions

Postoperative ileus (POI), especially following abdominal surgery where opioids are used for pain management, is a very common scenario where prokinetics are considered.

Alvimopan blocks µ-opioid receptors in the gut, which are typically activated by opioid pain medications to slow down bowel motility. By blocking these receptors, Alvimopan helps restore normal bowel function.

Neostigmine is particularly effective for stimulating colonic motility, making it suitable for the specific type of colonic dilation seen in ACPO. While it can also be used for other types of ileus, its use is more common and well-established in ACPO.

Their use for hastening the resolution of general postoperative ileus is controversial and not strongly supported by evidence. They are still used for other GI motility disorders, like gastroparesis, or for feeding intolerance in critically ill patients, but are less commonly recommended for paralytic ileus due to limited efficacy and significant side effect profiles.

Prokinetics carry various risks depending on the agent. Metoclopramide has risks of neurological side effects like tardive dyskinesia, while Neostigmine can cause bradycardia. Erythromycin carries cardiac risks, including QT prolongation.

Yes, many cases resolve with conservative, non-pharmacological management, which is the cornerstone of treatment. This includes supportive care (bowel rest, fluid/electrolyte management), minimizing opioids, early mobilization, and chewing gum.

Paralytic ileus is a temporary paralysis of the intestinal muscle, while a mechanical obstruction involves a physical blockage of the intestine. Prokinetics are only useful for paralytic ileus and are contraindicated in a mechanical obstruction.