Alvimopan
Alvimopan is a peripherally-acting mu-opioid receptor antagonist (PAMORA) that helps restore normal bowel function following abdominal or pelvic surgery by blocking opioid effects in the gastrointestinal tract.
Alvimopan reverses opioid-induced slowing of the intestines to accelerate recovery of bowel function after abdominal surgery.
This medication carries a boxed (black box) warning — the strongest type of FDA warning. Review the full prescribing information before use.
Key facts at a glance
- ATC
- A06AH02
- RxNorm
- 480639
- Generic
- Alvimopan
- Class
- atc-a06
- Brands
- Entereg
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- capsule
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 12mg once preoperatively
- Maximum
- consult physician
- Frequency
- single dose 30 minutes to 5 hours before surgery
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- not established
- Maximum
- consult physician
- Frequency
- not applicable
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 12mg once preoperatively
- Maximum
- consult physician
- Frequency
- single dose with caution in renal/hepatic impairment
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
9 groupspregnancy
first trimesteruse only if benefits outweigh risks
avoid use during pregnancy unless potential benefits justify potential risks to fetus
regular fetal monitoring recommended
Use with caution and monitor for adverse effects.
pregnancy
third trimesteruse only if benefits outweigh risks
avoid use near term due to potential effects on uterine contractility
fetal monitoring and uterine activity monitoring
Use with caution and monitor for adverse effects.
lactation
breastfeedingavoid or discontinue breastfeeding
not recommended during breastfeeding due to unknown excretion in breast milk
monitor infant for any adverse effects
geriatric
elderly 65 and olderno dosage adjustment required but use with caution
use with caution due to potential increased sensitivity and cardiovascular risks
monitor cardiovascular function and bowel recovery
Use with caution and monitor for adverse effects.
pediatric_age
children under 18not recommended
not indicated for use in pediatric patients safety and efficacy not established
not applicable
renal_impairment
severe creatinine clearance less than 30use with caution no specific dose adjustment in prescribing information
use cautiously in patients with severe renal impairment monitor for adverse effects
monitor renal function and clinical response
Use with caution and monitor for adverse effects.
renal_impairment
moderate creatinine clearance 30 60no dosage adjustment required
no dose adjustment needed for moderate renal impairment
routine monitoring
hepatic_impairment
severe hepatic impairmentuse with caution
use with caution in severe hepatic impairment due to limited data
monitor hepatic function and clinical response
Use with caution and monitor for adverse effects.
hepatic_impairment
moderate hepatic impairmentno dosage adjustment required
no dose adjustment needed for mild to moderate hepatic impairment
routine monitoring
Statistics and clinical data
FDA Approval Year
FDA approval date for Entereg
Drug class
Pharmacological classification
Indication
FDA-approved indication
Mechanism of action
Pharmacodynamic properties
Alvimopan is indicated for the treatment of postoperative ileus (POI) in adults following bowel resection or radical hysterectomy. It is used for short-term, in-hospital treatment to accelerate the time to first bowel movement and discharge readiness. It is specifically studied in patients receiving opioid analgesics for surgical pain management.
Alvimopan is a selective, competitive antagonist at the mu-opioid receptor with high affinity (Ki of 0.4 nM). It works peripherally in the gastrointestinal tract to block the inhibitory effects of opioids on intestinal motility and secretion. Because it does not cross the blood-brain barrier in significant amounts, it reverses gastrointestinal effects of opioids without reducing their central analgesic benefits.
Alvimopan is available only through a restricted access program (Risk Evaluation and Mitigation Strategy) due to potential cardiovascular risk with prolonged use. It should not be used in patients with complete mechanical bowel obstruction or those who have taken opioids chronically (beyond brief post-surgical use). Common adverse effects include dyspepsia, hypokalemia, and back pain. Treatment is typically initiated immediately before surgery and continued up to 7 days or until hospital discharge.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy