What is the treatment plan for an 86-year-old male with opioid-induced constipation?

Treatment Plan for Opioid-Induced Constipation in an 86-Year-Old Male

For an 86-year-old male with opioid-induced constipation, start with a stimulant laxative (senna 2 tablets daily) with or without a stool softener, along with adequate fluid intake and physical activity as tolerated. 1

Initial Assessment and Preventive Measures

• Rule out bowel obstruction and impaction before initiating treatment 1
• Discontinue any non-essential constipating medications 1
• Assess for other causes of constipation (hypercalcemia, hypokalemia, hypothyroidism, diabetes mellitus) 1

First-Line Treatment

• Prophylactic regimen:

  • Stimulant laxative: Senna, 2 tablets every morning (maximum 8-12 tablets per day) 1
  • Consider adding stool softener (docusate), although evidence suggests senna alone may be sufficient 1
  • Increase laxative dose when increasing opioid dose 1
  • Goal: One non-forced bowel movement every 1-2 days 1

• Lifestyle modifications:

  • Maintain adequate fluid intake 1
  • Maintain adequate dietary fiber if fluid intake is sufficient 1
  • Encourage physical activity/exercise if feasible 1
  • Note: Fiber supplements like Metamucil are unlikely to control opioid-induced constipation and are not recommended 1

Second-Line Treatment (If Constipation Persists)

• Reassess for cause and severity of constipation; rule out bowel obstruction 1

• Check for impaction 1

• Add or increase bisacodyl 10-15 mg daily to TID 1

• Consider adding osmotic laxatives:

  • Polyethylene glycol (PEG): 1 capful in 8 oz water twice daily 1
  • Lactulose: 30-60 mL daily to BID 1
  • Magnesium hydroxide: 30-60 mL daily 1
  • Magnesium citrate: 8 oz daily 1
  • Sorbitol: 30 mL every 2 hours × 3, then as needed 1

• Consider rectal interventions if needed:

  • Bisacodyl suppository (one rectally daily to BID) 1
  • Glycerin suppository 1
  • Fleet, saline, or tap water enema 1

• Consider adding prokinetic agent:

  • Metoclopramide 10-20 mg PO QID (use with caution due to risk of tardive dyskinesia in elderly) 1

Third-Line Treatment (For Laxative-Refractory OIC)

• Consider peripherally acting μ-opioid receptor antagonists (PAMORAs):

  • Methylnaltrexone 0.15 mg/kg subcutaneously every other day (no more than once daily) 1
  • Avoid in patients with postoperative ileus or mechanical bowel obstruction 1
  • Naloxegol 12.5-25 mg once daily (FDA approved for chronic non-cancer pain) 1, 2
  • Monitor for potential adverse effects: abdominal pain (12-21%), diarrhea (6-9%), nausea (7-8%) 2

• Consider opioid rotation to fentanyl or methadone, which may cause less constipation 1

Special Considerations for Elderly Patients

• Start with lower doses of medications and titrate slowly 3
• Monitor closely for adverse effects, particularly with stimulant laxatives 3
• Be cautious with magnesium-based laxatives due to potential toxicity in elderly patients with renal impairment 3
• Assess for fecal impaction more frequently, as it's common in elderly patients 3

Monitoring and Follow-up

• Use the Bowel Function Index to objectively evaluate severity and monitor response 1, 4
• A score of 30 or higher indicates clinically significant constipation 1
• Reassess bowel function regularly and adjust regimen as needed 1, 4
• Increase laxative doses if constipation worsens or if opioid doses are increased 1

Common Pitfalls to Avoid

• Waiting until constipation develops before starting a preventive regimen 5, 6
• Relying solely on increased fluid intake and dietary modifications without pharmacologic intervention 5, 4
• Using bulk-forming agents like psyllium as primary therapy (ineffective for OIC) 1
• Failing to increase laxative dose when opioid dose is increased 1
• Underestimating the impact of constipation on quality of life and medication adherence 5, 7