What is the recommended dose of MiraLAX (polyethylene glycol) for a 5-year-old child with constipation?

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MiraLAX Dosing for a 5-Year-Old Child with Constipation

The recommended dose of MiraLAX (polyethylene glycol 3350) for a 5-year-old child with constipation is approximately 0.5-0.8 g/kg/day, which typically translates to about 8-12 grams (½-¾ capful) mixed in 4-8 ounces of liquid daily. 1, 2

Dosing Guidelines

Weight-Based Dosing

  • The most effective maintenance dose for children is approximately 0.7-0.8 g/kg/day 1, 2
  • For a typical 5-year-old weighing 18-20 kg, this equals approximately:
    • 12-16 grams daily (¾-1 capful)
    • Start at the lower end of the range and adjust as needed

Administration Instructions

  • Mix the powder completely in 4-8 ounces of any beverage
  • Ensure the powder is fully dissolved before drinking
  • Can be given once daily at any time of day
  • Best given consistently at the same time each day

Treatment Duration and Monitoring

Initial Treatment Phase

  • Expect results within 24-48 hours
  • Continue daily dosing until regular bowel movements are established
  • Monitor for:
    • Frequency of bowel movements (goal: soft, non-painful stool every 1-2 days)
    • Consistency of stool (should be soft but formed)
    • Resolution of abdominal discomfort

Maintenance Phase

  • May need to continue treatment for several weeks to months
  • Dose can be adjusted based on response:
    • Decrease if stools become too loose
    • Increase if constipation persists

Safety Considerations

Advantages of MiraLAX

  • Non-habit forming
  • Tasteless and easily mixed with beverages
  • Well-tolerated in pediatric populations
  • Does not cause significant electrolyte disturbances

Potential Side Effects

  • Diarrhea (most common) - reduce dose if this occurs 1
  • Abdominal bloating or gas
  • No significant adverse effects on electrolytes or other laboratory values

Additional Management Recommendations

Dietary and Lifestyle Modifications

  • Increase fluid intake throughout the day
  • Encourage physical activity
  • Increase dietary fiber if fluid intake is adequate
  • Establish regular toileting habits

When to Consult a Healthcare Provider

  • If constipation persists despite appropriate dosing for 1 week
  • If abdominal pain becomes severe
  • If blood appears in the stool
  • If the child develops fever or vomiting

Important Caution

While the FDA label for MiraLAX states "children 16 years of age or under: ask a doctor" 3, pediatric gastroenterology guidelines and clinical research support its use in children with proper medical supervision. Always consult with your child's healthcare provider before starting treatment.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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