What is the treatment for constipation in an 18-month-old child?

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Treatment of Constipation in an 18-Month-Old Child

For an 18-month-old child with constipation, the first-line treatment should include increasing fluid intake, dietary modifications, and if needed, polyethylene glycol (PEG) as a safe and effective laxative option.

Initial Assessment and Non-Pharmacological Approaches

• Constipation in children is usually functional (caused by stool retention) rather than organic, but be alert for red flags that might indicate serious underlying conditions 1

• Increase fluid intake as a first step in managing constipation in young children 2

• Increase dietary fiber if the child has adequate fluid intake, as fiber can help improve stool consistency and frequency 2, 3

• Consider fruit juices that contain sorbitol, such as prune, pear, and apple juices, which can help increase stool frequency and water content in infants with constipation 2

• Rule out impaction, which may present with overflow diarrhea around the impacted stool 2

Pharmacological Management

• For infants over 6 months of age (including 18-month-olds), polyethylene glycol (PEG) is authorized, effective, and well-tolerated 4, 5

• PEG works by drawing water into the intestinal lumen, softening stool and increasing bowel movement frequency 1

• For children under 16 years, consult a doctor for proper PEG dosing as indicated on the FDA label 5

• If disimpaction is needed first (in case of severe constipation with hard stool):

  • Use a higher initial dose of PEG for the first few days 4, 6
  • After disimpaction, continue with maintenance therapy 1

• Alternative options if PEG is unavailable or not tolerated:

  • Lactulose can be used in children under 6 months and older 4
  • Mineral oil is another option but less commonly prescribed now 4
  • Glycerin suppositories may be considered for immediate relief 2

Duration of Treatment and Follow-up

• Treatment should be continued for a sufficient duration, often months, as relapse of functional constipation is common 1, 7

• The goal of treatment is one non-forced bowel movement every 1-2 days 2

• Maintenance medications should be gradually reduced rather than abruptly discontinued once regular bowel habits are established 6

Important Considerations and Cautions

• Avoid antimotility drugs like loperamide in children under 18 years of age with acute diarrhea 2

• If constipation persists despite appropriate treatment, consider referral for further evaluation to rule out organic causes 6

• For children with chronic constipation, education of the family and child about proper toileting habits is instrumental in improving outcomes 1, 7

• Despite appropriate treatment, only 50-70% of children with functional constipation demonstrate long-term improvement, highlighting the importance of consistent management 1

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

[Constipation in infants and children: How should it be treated?].

Archives de pediatrie : organe officiel de la Societe francaise de pediatrie, 2016

Research

Constipation in childhood.

Nature reviews. Gastroenterology & hepatology, 2011

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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