What is the recommended dosage of Miralax (polyethylene glycol) for a 12-month-old child?

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Miralax (Polyethylene Glycol) Dosing for a 12-Month-Old Child

For a 12-month-old child with constipation, Miralax (polyethylene glycol) is not FDA-approved, and you should consult with a pediatrician before use, as the FDA label states "children 16 years of age or under: ask a doctor." 1

Recommended Dosing When Prescribed by a Physician

When a physician determines Miralax is appropriate for a 12-month-old:

  • The typical starting dose is approximately 0.5-1 g/kg/day 2
  • For a 12-month-old (typically weighing 8-10 kg), this translates to roughly 4-10 g of Miralax powder daily 2
  • Mix the prescribed amount in 2-4 ounces of liquid (water, juice, or milk) 3
  • Ensure the powder is completely dissolved before giving to the child 1

Administration Tips

  • Give the dose once daily at the same time each day 3
  • Do not combine with starch-based thickeners used for difficult swallowing 1
  • Ensure the powder is fully dissolved before giving to the child 1
  • Do not give if there are any clumps in the solution 1

Duration of Treatment

  • Do not use for more than 7 days without physician supervision 1
  • Treatment of functional constipation typically requires sufficient dosing for an adequate period 4
  • Follow-up with the prescribing physician is essential to monitor effectiveness and adjust dosing as needed 4

Safety Considerations

  • Polyethylene glycol is generally well-tolerated in pediatric patients 2, 3
  • The most common side effect is diarrhea if the dose is too high 2
  • Monitor for proper hydration during treatment 4
  • If symptoms worsen or do not improve within 48-72 hours, contact your physician 4

Important Cautions

  • The FDA label specifically states to consult a doctor for children 16 years and under 1
  • Polyethylene glycol is more commonly used in children over 6 months of age, though dosing should be determined by a healthcare provider 4
  • For infants under 6 months with constipation, lactulose-based medications are typically the first-line treatment 4

Always follow the specific instructions provided by your child's healthcare provider, as they will tailor the dose to your child's specific needs and medical condition.

References

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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