Alvimopan

Generic name:

Alvimopan

Drug class:

Peripherally acting mu-opioid receptor antagonist (PAMORA)

Dosage form:

• Oral tablet: 12 mg

Route of administration:

Oral

Dose:

• 12 mg taken 30 minutes to 5 hours before surgery
• 12 mg twice daily postoperatively (morning and evening) for up to 7 days
• Maximum of 15 doses per treatment course

Mechanism of action:

Alvimopan selectively antagonizes peripheral mu-opioid receptors in the gastrointestinal tract without significant penetration of the blood–brain barrier, thereby reversing opioid-induced delay in gastrointestinal motility.

Drug usage cases:

• Approved for acceleration of gastrointestinal recovery after partial large or small bowel resection surgery with primary anastomosis
• Off-label: prevention of postoperative ileus after laparoscopic abdominal surgery
• Off-label: enhancement of postoperative bowel function in other major abdominal procedures

Drug contraindications:

• Therapeutic opioid use for more than 7 consecutive days prior to surgery
• Known or suspected gastrointestinal obstruction
• Hypersensitivity to alvimopan or any component of the formulation
• Use beyond 15 doses per treatment course due to increased cardiovascular risk

Side effects:

• Abdominal pain
• Dyspepsia
• Flatulence
• Diarrhea
• Nausea and vomiting
• Back pain
• Urinary retention
• Hypokalemia
• Dehydration
• Sepsis (postoperative context)
• Dizziness
• Anemia
• Hyperglycemia
• Myocardial infarction (rare, associated with extended use)

Warnings:

• Limit to a maximum of 15 doses to reduce risk of myocardial infarction
• Not for use in patients with chronic opioid dependence—may precipitate withdrawal
• Monitor for signs of gastrointestinal perforation or obstruction
• Use with caution in patients with cardiovascular disease
• Ensure adequate hydration and electrolyte monitoring
• Hypersensitivity reactions possible; discontinue if signs of anaphylaxis occur

Use during pregnancy or breastfeeding:

Animal reproduction studies have not demonstrated fetal harm, but no adequate and well-controlled studies exist in pregnant women. Use only if potential benefit justifies the potential risk to the fetus. It is unknown whether alvimopan is excreted in human milk; exercise caution when administering to nursing mothers.