What is the recommended dose of lactulose (a laxative medication) in grams for a 12-month-old child?

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Lactulose Dosing for a 12-Month-Old Child

For a 12-month-old child, the recommended dose of lactulose is 2.5-10 mL per day in divided doses, which corresponds to approximately 1.7-6.7 grams of lactulose daily.

Pediatric Dosing Guidelines

  • The FDA-approved initial daily oral dose of lactulose for infants is 2.5 mL to 10 mL in divided doses 1
  • For older children and adolescents, the total daily dose increases to 40-90 mL 1
  • Dosing should be adjusted based on clinical response with the goal of achieving 2-3 soft bowel movements per day 2
  • If the initial dose causes diarrhea, the dose should be reduced immediately 1
  • If diarrhea persists despite dose reduction, lactulose should be discontinued 1

Calculation of Grams from Volume

  • Standard lactulose solution contains approximately 667 mg of lactulose per mL 2
  • Therefore, 2.5-10 mL corresponds to approximately 1.7-6.7 grams of lactulose
  • This is significantly lower than adult dosing, which typically ranges from 20-30 grams (30-45 mL) per day 2, 3

Administration Considerations

  • Lactulose can be administered with water, milk, fruit juice or other beverages to improve palatability 2
  • Treatment should be continued for a sufficient duration to establish regular bowel patterns 4
  • The dose should be titrated to produce 2-3 soft stools daily 1

Monitoring and Adjustments

  • Monitor for excessive bowel movements which may indicate need for dose reduction 2
  • Watch for signs of dehydration, which can occur with excessive lactulose use 5
  • Bloating and flatulence are common dose-dependent side effects that may limit use 2

Alternative Options

  • For infants over 6 months of age, polyethylene glycol (PEG) is an authorized and effective alternative 4
  • Studies show PEG may decrease total colonic transit time more effectively than lactulose (47.6±2.7 vs 55.3±2.4 hours) 6
  • Lactitol can be used as an alternative at a dose of 250-400 mg/kg/day, which is almost half the dose of lactulose (500-750 mg/kg/day) for pediatric patients 7
  • Lactitol has shown fewer side effects such as abdominal pain and flatulence compared to lactulose in pediatric studies 7

Important Cautions

  • Overuse of lactulose can lead to complications including dehydration, hypernatremia, and severe perianal skin irritation 5
  • Low doses (below laxative threshold) may have prebiotic effects that can benefit gut health 8
  • Always start with the lower end of the dosing range and titrate up as needed based on clinical response 1

References

Guideline

Lactulose Dosage and Administration

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Lactulose Dosage and Administration Guidelines

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

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

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

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

[Lactitol in chronic idiopathic constipation in children].

La Pediatria medica e chirurgica : Medical and surgical pediatrics, 1995

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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