What are the alternatives to oxymorphone (OxyContin) for managing constipation?

Alternatives to OxyContin for Managing Constipation

For opioid-induced constipation, the most effective alternatives include traditional laxatives as first-line treatment, followed by peripherally acting μ-opioid receptor antagonists (PAMORAs) like methylnaltrexone or naloxegol for refractory cases. 1

First-Line Treatment Options

• Begin with lifestyle modifications including increased fluid intake, regular physical activity, and toileting as soon as possible in response to the urge to defecate 1
• Add a stimulant laxative such as bisacodyl (10-15 mg, 2-3 times daily) with a goal of one non-forced bowel movement every 1-2 days 1, 2
• Consider adding osmotic laxatives if constipation persists:
  • Polyethylene glycol (PEG) produces a bowel movement within 1-3 days 3, 1
  • Lactulose or magnesium citrate can be effective alternatives 1, 4
• Stool softeners like docusate sodium may be added, generally producing a bowel movement within 12-72 hours 5, 4

Second-Line Treatment Options

• For persistent constipation, consider rectal interventions such as:
  • Glycerin suppositories for impaction 1
  • Rectal bisacodyl once daily 1, 6
• If gastroparesis is suspected, add a prokinetic agent like metoclopramide 1, 2

Third-Line Treatment Options (For Refractory OIC)

• Peripherally acting μ-opioid receptor antagonists (PAMORAs) are specifically designed to target the underlying mechanism of opioid-induced constipation while preserving pain control 1, 7, 8:
  • Methylnaltrexone 0.15 mg/kg subcutaneously every other day (no more than once daily) 1, 2
  • Naloxegol for patients with chronic non-cancer pain 1, 2
• Secretagogues may be considered:
  • Lubiprostone activates chloride channels to enhance intestinal fluid secretion 1, 7
  • Linaclotide is a guanylate cyclase-C receptor agonist effective for chronic constipation 1, 7

Alternative Strategies

• Consider opioid rotation to less constipating opioids (e.g., transdermal fentanyl causes less constipation than oral morphine) 1, 2
• For severe cases, combination therapy may be necessary (e.g., lubiprostone with methylnaltrexone) 1, 7
• Erythromycin or azithromycin may help with small bowel dysmotility in some cases 1

Important Considerations

• Always rule out impaction, obstruction, and other treatable causes of constipation (hypercalcemia, hypokalemia, hypothyroidism, diabetes mellitus) before initiating treatment 1, 2
• PAMORAs should not be used in patients with postoperative ileus or mechanical bowel obstruction 1, 7
• Monitor for diarrhea with secretagogues, which can lead to dehydration 7
• Increase fiber intake slowly over several weeks to minimize adverse effects like bloating 4, 9

Following this algorithmic approach will help manage constipation effectively while maintaining pain control with opioids, improving patient quality of life and reducing morbidity associated with untreated constipation.