What are the management options for constipation?

Management Options for Constipation

First-line treatment for constipation should include polyethylene glycol (PEG) 17g daily mixed in 120-240ml of liquid, which is strongly recommended based on high-quality evidence. 1

Initial Assessment and General Approach

• Evaluate for potential causes of constipation:

  • Medication side effects (especially opioids)
  • Pelvic floor dysfunction
  • Mechanical obstruction
  • Metabolic abnormalities
  • Other diseases or medications

• Rule out warning signs requiring further investigation:

  • Rectal bleeding
  • Weight loss
  • Sudden change in bowel habits
  • Severe abdominal pain

Treatment Algorithm

Step 1: Lifestyle Modifications

• Increase dietary fiber intake to 20-25g daily, preferably using psyllium 1, 2
  • Gradually increase over several weeks to minimize bloating
  • Stop if rectal bleeding occurs or constipation persists beyond 7 days
• Ensure adequate fluid intake (at least 8 glasses of water daily) 1
• Promote regular physical activity within patient's limitations 1
• Establish regular toileting habits, especially after meals 1, 3

Step 2: Osmotic Laxatives

• Polyethylene glycol (PEG) 17g daily is the preferred first-line agent 1
  • Mix in 120-240ml of liquid
  • Discontinue if diarrhea, rectal bleeding, or worsening abdominal pain occurs 4
  • Should not be used for more than one week without medical supervision 4
• Alternative: Lactulose 30-60mL BID-QID 1

Step 3: Bulk-Forming Laxatives

• Methylcellulose or psyllium supplements 1, 5, 2
  • Effective for adding fiber and relieving constipation
  • Methylcellulose may cause less gas than other fiber supplements 5
  • Stop use if constipation lasts more than 7 days or rectal bleeding occurs 2

Step 4: Stimulant Laxatives

• Bisacodyl 10-15mg daily to TID 1
• Sennosides
• Target: one non-forced bowel movement every 1-2 days

Step 5: Special Situations

For Opioid-Induced Constipation (OIC):

• Ensure appropriate indication for opioid therapy and use minimum necessary dose 6
• Consider "opioid switching" to less constipating alternatives (e.g., transdermal fentanyl instead of oral morphine) 6
• Consider peripherally acting μ-opioid receptor antagonists (PAMORAs) for refractory cases 3

For Defecatory Disorders:

• Biofeedback therapy is highly effective (>70% improvement) 1
  • Trains patients to relax pelvic floor muscles during straining
  • Improves rectoanal coordination

When to Consider Further Testing

If constipation persists despite 4-6 weeks of appropriate management:

• Anorectal manometry to identify anal weakness and rectal sensation issues 1
• Colonic transit studies to diagnose slow-transit constipation 1
• Plain abdominal radiography to evaluate fecal load and rule out obstruction 1

Special Considerations

Elderly Patients

• Higher risk of impaction and complications 3
• May present with atypical symptoms
• Complete medication review essential 3
• Avoid long-term use of magnesium-based laxatives due to potential toxicity 3

Children

• Common causes include inadequate fiber/fluid intake and withholding behavior 1
• Assess for underlying medical conditions (hypothyroidism, neurological disorders) 1
• Evaluate for anal fissures or stenosis that may cause pain with defecation 1

Surgical Options

• Reserved for severe cases unresponsive to aggressive medical management 1
• Only about 5% of constipation cases ultimately require surgical intervention 1
• Options include total colectomy with ileorectal anastomosis for severe slow-transit constipation 1
• Surgical correction of anatomical defects (rectocele, rectal prolapse) when identified 1

Remember that constipation treatment should follow a stepwise approach, starting with lifestyle modifications and progressing to medications only if necessary. Most cases can be effectively managed with dietary changes and over-the-counter laxatives.