What are the management options for constipation?

Management of Constipation in the Emergency Department

Polyethylene glycol (PEG) is the recommended first-line treatment for constipation in the emergency department setting, with strong evidence supporting its efficacy and safety. 1, 2

Initial Assessment

• Define constipation: Less than 3 bowel movements per week or straining during >25% of bowel movements 1, 3

• Key symptoms to evaluate:

  • Stool consistency (using Bristol Stool Form Scale)
  • Frequency of bowel movements
  • Straining during defecation
  • Sensation of incomplete evacuation
  • Abdominal pain or discomfort

• Rule out bowel obstruction with these differentiating features:

  Feature	Constipation	Partial Bowel Obstruction
  Pain	Dull, crampy, intermittent	Colicky, more severe, periodic
  Stool	Hard, infrequent	May have complete absence
  Vomiting	Uncommon	Common
  Distension	Mild to moderate	More pronounced, sudden onset

Treatment Algorithm

First-Line Treatment

1. Osmotic Laxatives
   • PEG 17.5g dissolved in 250mL water twice daily 1, 2
   • Response to PEG has been shown to be durable over 6 months 1
   • Side effects: abdominal distension, loose stool, flatulence, and nausea 1

Second-Line Options

1. Stimulant Laxatives

   • Bisacodyl 10-15mg daily to TID 2
   • Sennosides

2. Bulk-Forming Agents (for mild constipation)

   • Psyllium (most evidence among fiber supplements) 1, 2
   • Should be taken with 8-10 ounces of fluid 1
   • May cause flatulence as side effect 1

3. Stool Softeners

   • Docusate sodium

For Opioid-Induced Constipation

• Consider peripherally restricted μ-opiate antagonists 4
• Consider "opioid switching" to less constipating alternatives (e.g., transdermal fentanyl instead of oral morphine) 2

For Refractory Cases

• Enemas if oral treatment fails after several days 1
  • Small-volume self-administered enemas
  • Larger volume clinician-administered enemas should be given by experienced professionals 1
  • Contraindications: neutropenia, thrombocytopenia, paralytic ileus, intestinal obstruction, recent colorectal surgery, severe colitis, toxic megacolon 1

Special Considerations

Lifestyle Modifications

• Increase dietary fiber intake to 20-25g daily 2
• Increase fluid intake to at least 8 glasses of water daily 2
• Promote physical activity within patient's limitations 2
• Ensure privacy and comfort for defecation 1
• Proper positioning (using a small footstool may help) 1

Elderly Patients

• Require careful assessment due to higher risk of impaction and complications 2
• May present with atypical symptoms
• Complete medication review essential 2

Diagnostic Tests When Initial Management Fails

• Plain abdominal radiography to evaluate fecal load and rule out obstruction 2
• CT scan with contrast for suspected obstruction 2
• Consider colonic transit studies for suspected slow-transit constipation 2

Key Pitfalls to Avoid

1. Missing bowel obstruction - Always rule out obstruction before aggressive treatment
2. Inadequate fluid intake with fiber supplements - Ensure patients take fiber with sufficient water to prevent worsening constipation
3. Overuse of stimulant laxatives - Can lead to dependency and decreased bowel function
4. Ignoring medication-induced constipation - Review patient's medication list for constipating drugs
5. Using enemas in contraindicated conditions - Risks include perforation, rectal mucosal damage, and bacteremia 1

The evidence strongly supports PEG as first-line therapy for constipation management in the emergency setting, with multiple high-quality studies demonstrating its efficacy and safety profile 1, 2, 5, 4. When implementing a treatment plan, consider the underlying cause of constipation and tailor therapy accordingly.