Can rifaximin be given to children?

Rifaximin Use in Children

Rifaximin is not FDA-approved for use in children under 12 years of age, and its safety and effectiveness have not been established in pediatric patients less than 12 years of age for traveler's diarrhea or in patients less than 18 years of age for hepatic encephalopathy and irritable bowel syndrome with diarrhea (IBS-D) 1.

FDA Approval Status and Safety

The FDA label for rifaximin (Xifaxan) clearly states that safety and effectiveness have not been established in:

• Children under 12 years for traveler's diarrhea
• Children under 18 years for hepatic encephalopathy and IBS-D

This lack of approval is primarily due to insufficient clinical data in pediatric populations rather than specific safety concerns.

Clinical Use in Specific Conditions

Clostridium difficile Infection

For pediatric C. difficile infection, the 2018 IDSA/SHEA guidelines provide specific recommendations:

• For second or subsequent recurrences of C. difficile infection in children, vancomycin followed by rifaximin may be considered as a treatment option 2
• However, the guidelines specifically note that "no pediatric dosing for rifaximin" exists and that rifaximin is "not approved by the US Food and Drug Administration for use in children <12 years of age" 2

Inflammatory Bowel Disease

Some limited research suggests potential benefit in pediatric inflammatory bowel disease:

• A small retrospective review showed that rifaximin at doses of 10-30 mg/kg was well-tolerated in children with IBD 3
• Larger doses showed better results for abdominal pain relief in this small study 3

Pharmacokinetic Considerations

Rifaximin has favorable pharmacokinetic properties that make it theoretically suitable for pediatric use:

• Minimal systemic absorption (<0.4%) 4
• High concentration in the intestinal lumen 4
• Limited systemic adverse effects due to poor absorption 5

Clinical Decision Making

When considering rifaximin use in children:

1. Age-based approach:

   • For children ≥12 years: May use rifaximin for traveler's diarrhea following adult dosing guidelines
   • For children ≥18 years: May use for all approved indications (traveler's diarrhea, hepatic encephalopathy, IBS-D)
   • For children <12 years: Not FDA-approved; use should be limited to specific circumstances under specialist guidance

2. Off-label considerations:

   • For recurrent C. difficile infection: Consider as part of a treatment regimen in children who have failed standard therapies, following the IDSA/SHEA guidelines 2
   • For inflammatory bowel disease: Limited evidence suggests potential benefit, but should be used only under specialist guidance 3

Common Pitfalls and Caveats

• Dosing uncertainty: No standardized pediatric dosing exists for children under 12 years
• Regulatory compliance: Off-label use requires thorough documentation and informed consent
• Antimicrobial stewardship: Despite minimal absorption, inappropriate use could potentially contribute to antimicrobial resistance
• Cost considerations: Rifaximin is expensive and may not be covered by insurance for off-label pediatric use

Conclusion

While rifaximin appears to have a favorable safety profile due to its minimal systemic absorption, its use in children under 12 years should be approached with caution and limited to specific clinical scenarios where potential benefits outweigh risks, preferably under specialist guidance. For children 12 years and older, rifaximin may be used for traveler's diarrhea according to FDA approval, and for those 18 and older, it may be used for all approved indications.