Is it safe to give probiotics, such as Lactobacillus reuteri, to a preterm infant born at 35-36 weeks gestational age (GA) for colic?

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Probiotics for Preterm Infant (35-36 Weeks) with Colic

Yes, Lactobacillus reuteri DSM 17938 is safe and can be given to your preterm infant born at 35-36 weeks gestational age for colic, based on AGA guidelines that specifically recommend L. reuteri for preterm infants less than 37 weeks gestational age. 1

Primary Recommendation

The American Gastroenterological Association (AGA) 2020 guidelines explicitly recommend L. reuteri (DSM 17938 or ATCC 55730) as one of the acceptable probiotic options for preterm infants less than 37 weeks gestational age. 1 Your infant at 35-36 weeks falls within this category, making L. reuteri an appropriate choice.

Evidence Supporting Use in This Population

Safety Profile in Preterm Infants

  • L. reuteri DSM 17938 has been extensively studied in preterm infants with demonstrated safety, showing no increased risk of sepsis in studies involving over 10,000 preterm infants. 2
  • The strain has been tested specifically in extremely low birthweight infants (<1,000g) born at <28 weeks GA, showing favorable safety outcomes. 1
  • No cases of culture-proven sepsis with the probiotic organism have been reported in clinical trials. 1

Efficacy for Colic

  • L. reuteri DSM 17938 significantly reduces daily crying time in infants with colic, with one study showing reduction from 200.9 minutes/day to 32.1 minutes/day (p<0.01). 3
  • Treatment success (≥50% reduction in crying) was achieved in 100% of infants receiving L. reuteri compared to 15.7% receiving placebo. 3
  • Crying time reduction was significant even during the first week of therapy initiation. 3

Additional Benefits in Preterm Infants

  • L. reuteri DSM 17938 shortens hospitalization by 7.89 days (95% CI -11.60 to -4.17) based on moderate-to-high quality evidence. 1
  • The probiotic reduces time to reach full enteral feeds by 2.62 days (95% CI -4.53 to -0.71). 1
  • Supplementation is associated with improved head growth at 36 weeks postmenstrual age and weight gain at 2 years. 1

Practical Implementation

Dosing

  • Standard dose: 1 × 10⁸ to 1.25 × 10⁸ CFU daily 1
  • Continue treatment for at least 21 days for colic management 3

Product Selection

  • Choose pharmaceutical-grade products rather than dietary supplements to minimize contamination risk, as manufacturing contaminants have caused fatal infections in preterm infants. 2, 4
  • Verify the specific strain designation (DSM 17938) on the product label 1

Monitoring

  • Assess crying time reduction within the first week of treatment 3
  • Monitor for any signs of sepsis, though risk is extremely low 1, 2

Important Caveats

Contraindications and High-Risk Situations

Exercise extreme caution or avoid use if your infant has: 1, 5, 4

  • Immunocompromised status
  • Indwelling central venous catheter
  • Cardiac valvular disease
  • Short-gut syndrome

Alternative Considerations

If L. reuteri is unavailable or contraindicated, the AGA also recommends: 1

  • Combination products containing Lactobacillus species and Bifidobacterium species
  • B. animalis subsp. lactis alone (which may offer superior reduction in hospitalization days) 2, 4
  • L. rhamnosus (ATCC 53103 or LCR 35) in combination with Bifidobacterium species 1, 4

Microbiome Effects Supporting Safety

  • L. reuteri DSM 17938 supplementation increases beneficial Lactobacillaceae abundance while reducing potentially pathogenic Enterobacteriaceae and Staphylococcus species. 1
  • The colonization is transient but creates conditions conducive to infant growth through competitive exclusion processes. 1
  • Effects on bacterial community composition may be hospital-specific, influenced by local clinical practices. 1

Quality of Evidence

The recommendation is based on: 1

  • Moderate-to-high quality evidence for safety and efficacy in preterm infants
  • Conditional recommendation from AGA guidelines (2020)
  • Multiple randomized controlled trials and observational studies 1, 3

Your infant at 35-36 weeks gestational age meets the criteria for safe L. reuteri supplementation, and this probiotic has demonstrated efficacy specifically for colic management while also providing additional benefits for preterm infant health outcomes.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Bifidobacterium animalis Safety and Efficacy in Preterm Neonates

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Lactobacillus rhamnosus in Preterm Neonates

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Probiotic Use of Lactobacillus rhamnosus and Lactobacillus acidophilus

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

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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