What is the dosage of lactulose (a laxative) in a 6-month-old infant?

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From the FDA Drug Label

Pediatric: Very little information on the use of lactulose in young children and adolescents has been recorded. As with adults, the subjective goal in proper treatment is to produce 2 or 3 soft stools daily. On the basis of information available, the recommended initial daily oral dose in infants is 2. 5 mL to 10 mL in divided doses. The recommended initial daily oral dose of lactulose in a 6-month-old baby is 2.5 mL to 10 mL in divided doses, with the goal of producing 2 or 3 soft stools daily 1.

  • The dose may need to be adjusted based on the infant's response to the medication.
  • If the initial dose causes diarrhea, the dose should be reduced immediately.
  • If diarrhea persists, lactulose should be discontinued.

From the Research

Lactulose syrup should not be given to a 6-month-old baby without a pediatrician's prescription, as it can cause gas, bloating, and diarrhea, and improper dosing may lead to electrolyte imbalances or dehydration. For constipation in infants this young, first-line approaches include:

  • Ensuring adequate fluid intake, especially breast milk or formula
  • Offering small amounts of water if the baby has started solids
  • Considering prune, pear, or apple juice (1-2 ounces diluted with water) if the pediatrician approves If medication becomes necessary, the pediatrician might prescribe lactulose at a very specific dose tailored to the infant's weight, typically starting at 2.5-5 ml once or twice daily, as supported by a study on the treatment of pediatric constipation 2. Lactulose works by drawing water into the intestines and softening stool, making it easier to pass. However, it is crucial to follow medical guidance to avoid complications. Always consult your baby's doctor before giving any medication to an infant this young. Other studies, such as those on constipation in adults 3, 4, and a literature review of laxatives 5, may provide additional information, but the most relevant and recent guidance for pediatric constipation is found in 2. Additionally, a study on opioid-induced constipation 6 highlights the importance of careful laxative selection and dosing to avoid exacerbating constipation.

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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