What are the treatment options for constipation?

Treatment Options for Constipation

The preferred first-line treatment for constipation includes osmotic laxatives (particularly polyethylene glycol/PEG) or stimulant laxatives (such as senna, bisacodyl), with PEG having the strongest evidence for effectiveness and safety. 1, 2

Assessment and Diagnosis

Before initiating treatment, proper assessment should include:

• Complete medication review to identify potential causative medications
• Physical examination including abdominal examination, perineal inspection, and digital rectal examination (DRE)
• Evaluation for possible causes (thyroid dysfunction, hypercalcemia)
• Plain abdominal X-ray may be useful to assess fecal loading and exclude obstruction in severe cases 1

Treatment Algorithm

Step 1: Non-Pharmacological Interventions

• Lifestyle modifications:
  • Ensure privacy and comfort for defecation
  • Proper positioning (small footstool to assist gravity)
  • Increased fluid intake
  • Increased physical activity within patient limits
  • Establish regular toileting routine (attempt defecation 30 minutes after meals) 1
  • Abdominal massage (shown to reduce gastrointestinal symptoms and improve bowel efficiency, particularly in patients with neurogenic problems) 1, 3

Step 2: Pharmacological Interventions

• First-line options:

  • Osmotic laxatives: PEG (17-34g daily), lactulose, magnesium salts 1, 2
  • Stimulant laxatives: senna, cascara, bisacodyl (10-15mg daily), sodium picosulfate 1, 2

• Special situations:

  • For fecal impaction: Suppositories and enemas are preferred first-line when DRE identifies a full rectum or impaction 1
  • For opioid-induced constipation (OIC):
    • Prophylactic laxative therapy should be prescribed with opioid analgesics
    • Osmotic or stimulant laxatives are preferred
    • Avoid bulk laxatives (psyllium) in OIC 1, 2
    • For refractory OIC, consider peripheral opioid antagonists (PAMORAs) 1, 2

Step 3: For Refractory Constipation

• Evaluate for defecatory disorders or slow-transit constipation using specialized tests 4
• For defecatory disorders: Consider biofeedback therapy and pelvic floor retraining 2, 4
• For severe slow-transit constipation: Consider referral to specialized centers for colonic manometry 2

Important Considerations and Cautions

• Duration of treatment: Laxatives should generally not be used for longer than 1 week without medical supervision 5
• Contraindications for enemas: Neutropenia, thrombocytopenia, paralytic ileus, intestinal obstruction, recent colorectal surgery, anal/rectal trauma, severe colitis, abdominal inflammation/infection 1
• Medication precautions:
  • Magnesium salts should be used cautiously in renal impairment 1
  • Monitor for side effects: rectal bleeding, worsening abdominal pain, bloating, or cramping 5

Special Populations

Elderly Patients

• Ensure access to toilets, especially with decreased mobility
• Provide dietetic support
• Manage decreased food intake that affects stool volume and consistency
• Optimize toileting routine (attempt defecation twice daily, strain no more than 5 minutes) 1

Patients with Cancer

• All cancer patients should be evaluated for constipation
• Anticipatory management of constipation when opioids are prescribed
• For OIC, consider combined opiate/naloxone medications 1

Red Flags Requiring Immediate Attention

• Rectal bleeding
• Severe abdominal pain or distension
• Persistent constipation despite appropriate interventions
• Signs of obstruction or perforation 1, 2

While fiber supplements like psyllium and methylcellulose are available for constipation relief 6, 7, they are not recommended as first-line therapy, particularly in opioid-induced constipation 1. The evidence strongly supports osmotic laxatives (particularly PEG) and stimulant laxatives as more effective options with better safety profiles for most patients with constipation 1, 2, 4.