What are the treatment options for constipation, including laxatives?

Treatment Options for Constipation

For most patients with constipation, osmotic laxatives (polyethylene glycol, lactulose, or magnesium salts) or stimulant laxatives (senna, bisacodyl, sodium picosulfate) are the preferred first-line pharmacological treatments. 1, 2

Non-Pharmacological Approaches

• Increase fluid intake to improve stool consistency and ease passage 1, 2
• Increase dietary fiber if patient has adequate fluid intake and physical activity 1, 2
• Increase physical activity and mobility within patient limits to stimulate bowel function 1, 2
• Ensure proper positioning during defecation (using a small footstool can help apply pressure more effectively) 1, 2
• Provide privacy and comfort to allow normal defecation 1, 2
• Consider abdominal massage, which can reduce gastrointestinal symptoms and improve bowel efficiency, particularly in patients with neurogenic problems 1, 3

Pharmacological Treatment Algorithm

First-Line Options:

• Osmotic Laxatives:

  • Polyethylene glycol (PEG): Well-tolerated and effective, especially in elderly patients (17g/day) 1, 2
  • Lactulose: 30-60 mL BID-QID 1, 2
  • Magnesium salts (hydroxide: 30-60 mL daily-BID; citrate: 8 oz daily) 1, 2
  • Caution: Magnesium salts should be used cautiously in patients with renal impairment due to risk of hypermagnesemia 1

• Stimulant Laxatives:

  • Senna (with or without docusate): 2-3 tablets BID-TID 1, 2
  • Bisacodyl: 10-15 mg daily-TID, with goal of one non-forced bowel movement every 1-2 days 1
  • Sodium picosulfate 1

Second-Line Options (for refractory cases):

• Rectal Interventions (when digital rectal exam identifies a full rectum or fecal impaction):

  • Glycerine or bisacodyl suppositories (one rectally daily-BID) 1
  • Mineral oil retention enema 1
  • Tap water enema until clear 1

• Prokinetic Agents:

  • Metoclopramide: 10-20 mg PO QID 1
  • Linaclotide: 72-290 mcg once daily on empty stomach (at least 30 minutes before first meal) 4

For Opioid-Induced Constipation:

• Prophylactic laxative therapy should be initiated when starting opioids 1, 2
• Avoid bulk laxatives such as psyllium 1
• For refractory cases, consider methylnaltrexone 0.15 mg/kg subcutaneously every other day (not more than once daily) 1, 2

Special Situations

Fecal Impaction:

• Perform manual disimpaction following pre-medication with analgesic and/or anxiolytic 1
• After disimpaction, implement a maintenance bowel regimen to prevent recurrence 1

Elderly Patients:

• Ensure access to toilets, especially for those with decreased mobility 1
• Provide dietetic support to address decreased food intake 1
• Educate patients to attempt defecation at least twice daily, 30 minutes after meals, and to strain no more than 5 minutes 1
• Avoid liquid paraffin in bed-bound patients and those with swallowing disorders due to risk of aspiration pneumonia 1

Important Considerations

• Always rule out impaction or obstruction before aggressive treatment (physical exam, abdominal x-ray) 1, 2
• Discontinue non-essential constipating medications 1, 2
• Treat underlying causes such as hypercalcemia, hypokalemia, hypothyroidism, or diabetes mellitus 1
• Monitor patients on diuretics or cardiac glycosides for dehydration and electrolyte imbalances 1
• Enemas are contraindicated in patients with neutropenia, thrombocytopenia, paralytic ileus, intestinal obstruction, recent colorectal or gynecological surgery, anal/rectal trauma, severe colitis, abdominal inflammation/infection, toxic megacolon, undiagnosed abdominal pain, or recent pelvic radiotherapy 1

By following this structured approach to constipation management, clinicians can effectively address this common condition while minimizing complications and improving patient quality of life.