Entereg

Generic name:

Alvimopan

Drug class:

Peripherally acting μ-opioid receptor antagonist

Dosage form:

12 mg oral tablet

Root of administration:

Oral

Dose:

12 mg administered 30 minutes to 5 hours prior to surgery, then 12 mg twice daily for up to 7 days or maximum of 15 doses

Mechanism of action:

Selective μ-opioid receptor antagonist that acts in the gastrointestinal tract to counteract opioid-induced inhibition of GI motility without affecting central analgesia

Drug usage cases:

• Accelerating recovery of bowel function following partial large or small bowel resection with primary anastomosis
• Off-label: opioid-induced constipation (varies by indication; consult label)

Drug contra indications:

• Known or suspected gastrointestinal obstruction
• Patients who have received therapeutic doses of opioids for >7 consecutive days prior to surgery
• Hypersensitivity to alvimopan or any component of the formulation

Side effects:

• Dyspepsia
• Nausea
• Diarrhea
• Abdominal bloating
• Flatulence
• Vomiting
• Constipation
• Back pain
• Headache
• Urinary retention
• Hypokalemia
• Anemia
• Urinary tract infection
• Serious risk of cardiovascular events if used >15 doses (e.g., myocardial infarction)

Warnings:

• Limit use to hospitalized patients due to risk of gastrointestinal perforation
• Do not exceed 15 total doses; prolonged use increases risk of myocardial infarction
• Use with caution in patients with cardiovascular disease
• Monitor for signs of opioid withdrawal if patient is opioid-dependent
• Not recommended for use in pediatric patients
• Use caution in patients with severe hepatic impairment

Use during pregnancy or breastfeeding:

Pregnancy: Animal studies have shown no teratogenic effects; however, adequate and well-controlled studies in pregnant women are lacking. Use only if clearly needed and after risk-benefit assessment.

Breastfeeding: It is unknown whether alvimopan is excreted in human milk. Caution should be exercised, and benefits of breastfeeding should be weighed against the mother’s need for the drug and potential risks to the infant.