What is the recommended laxative treatment for pediatric constipation?

Treatment of Pediatric Constipation

Polyethylene glycol (PEG) is the preferred first-line laxative treatment for pediatric constipation in children over 6 months of age, while lactulose is recommended for infants under 6 months. 1

Initial Management Approach

• Increase fluid intake and dietary fiber as first steps in managing pediatric constipation 1
• For infants under 6 months of age, lactulose is the recommended osmotic laxative 1, 2
• For children over 6 months, polyethylene glycol (PEG) is the preferred osmotic laxative due to superior efficacy compared to other laxatives 1, 3
• PEG works as an osmotic laxative that draws water into the intestinal lumen to soften stool and increase bowel movements 4

Treatment Algorithm

Step 1: Assess for Fecal Impaction

• If fecal impaction is present, disimpaction should be performed first before maintenance therapy 5
• Disimpaction options include:
  • High-dose PEG for several days 2
  • Glycerin suppositories with or without mineral oil retention enema 6

Step 2: Maintenance Therapy

• For infants under 6 months:

  • Lactulose 30-60 mL BID-QID 6, 2

• For children over 6 months:

  • PEG (1 capful/8 oz water BID) as first-line therapy 6, 1
  • Alternative options if PEG is unavailable or not tolerated:
    • Lactulose 30-60 mL BID-QID 6
    • Sorbitol 30 mL every 2 hours × 3, then as needed 6
    • Magnesium hydroxide 30-60 mL daily-BID 6
    • Magnesium citrate 8 oz daily 6

Step 3: Behavioral and Dietary Interventions

• Establish proper toilet posture with foot and buttock support 1
• Implement a regular toileting program 1
• Increase dietary fiber if patient has adequate fluid intake 6
• Consider prune, pear, or apple juices which contain sorbitol to help increase stool frequency and water content 6

Important Considerations

• Treatment must be continued long-term (often months) to prevent relapse, as premature discontinuation is a common pitfall 1, 5
• Dosing should be adjusted based on clinical response rather than using fixed doses 5
• Children who undergo colonic evacuation followed by daily laxative therapy show better outcomes than those treated less aggressively 5
• Despite appropriate treatment, 30-50% of children may continue to have symptoms after 2 months of therapy 5, 7

Special Situations

• For opioid-induced constipation, consider methylnaltrexone 0.15 mg/kg subcutaneously every other day (except in post-operative ileus and mechanical bowel obstruction) 6
• In cases of persistent constipation despite standard therapy, consider prokinetic agents such as metoclopramide 10-20 mg PO QID 6
• For constipation with overflow diarrhea, rule out impaction through physical exam and abdominal x-ray 6