What are the treatment options for constipation?

Treatment Options for Constipation

Polyethylene glycol (PEG) at a dose of 17g daily is the recommended first-line treatment for constipation due to its proven efficacy, safety profile, and durable response. 1

First-Line Treatment Options

Osmotic Laxatives

• Polyethylene glycol (PEG)

  • Dosage: 17-34g daily
  • Response time: 1-3 days
  • Side effects: Bloating, abdominal discomfort, cramping
  • Caution: Should not be used for more than 1 week without medical consultation 2
  • Can be increased to 34g daily if needed 1

• Alternative Osmotic Laxatives

  • Lactulose: 15-30ml twice daily
  • Magnesium oxide: 400-500mg daily (avoid in renal impairment) 1

Stimulant Laxatives

• Bisacodyl

  • Dosage: 10-15mg daily
  • Best for short-term or rescue therapy 1
  • Goal: One non-forced bowel movement every 1-2 days 3

• Other Stimulant Options

  • Sodium picosulfate
  • Senna: 8.6-17.2mg daily 1
  • Caution: Prolonged use can lead to dependence and electrolyte imbalances 1

Lifestyle Modifications

• Physical Activity

  • Increase physical activity within patient limits 3, 1
  • Even bed-to-chair movement can be beneficial for severely limited patients 3

• Proper Toileting

  • Establish a regular toileting routine
  • Use proper positioning (footstool to elevate knees above bottom) 1
  • Ensure privacy and comfort 3
  • Attempt defecation 30 minutes after meals 3

• Dietary Changes

  • Ensure adequate hydration, especially when increasing fiber 1
  • Consider fiber supplementation (e.g., psyllium) at 100mg/kg body weight daily (max 5g/day) 4
  • Caution: Stop fiber use if constipation persists beyond 7 days or if rectal bleeding occurs 5

Special Considerations

Opioid-Induced Constipation

• All patients receiving opioid analgesics should be prescribed a concomitant laxative 3
• Osmotic or stimulant laxatives are generally preferred 3
• Avoid bulk laxatives such as psyllium for opioid-induced constipation 3
• Consider methylnaltrexone 0.15mg/kg subcutaneously every other day for refractory cases 3, 1

Fecal Impaction

• Suppositories and enemas are preferred first-line therapy when digital rectal examination identifies a full rectum or fecal impaction 3
• Digital disimpaction may be necessary, followed by maintenance bowel regimen 3

Treatment Algorithm

1. Initial Approach:

   • Start with PEG 17g daily
   • Implement lifestyle modifications (hydration, physical activity, proper toileting)
   • Reassess after 2-3 days

2. If Insufficient Response:

   • Increase PEG to 34g daily OR
   • Add a stimulant laxative (bisacodyl 10-15mg daily)

3. For Persistent Constipation:

   • Rule out fecal impaction (perform rectal examination)
   • Consider alternative osmotic laxatives (lactulose, magnesium)
   • For opioid-induced constipation, add methylnaltrexone if standard laxatives fail

4. When to Seek Further Evaluation:

   • Constipation lasting more than 7 days despite treatment
   • Rectal bleeding
   • Failure to have bowel movements
   • Worsening abdominal pain or bloating 5, 2

Monitoring and Follow-up

• Monitor for stool frequency and consistency
• Watch for abdominal discomfort and rectal bleeding
• Evaluate treatment success by achieving ≥3 bowel movements/week with minimal straining 3

Refractory Constipation

• For documented slow-transit constipation failing aggressive medical management, consider referral for specialized testing 1
• For defecatory disorders, pelvic floor retraining by biofeedback therapy is recommended rather than continued laxative use 1