What is the recommended dose of Pepcid (famotidine) for a 1-year-old child weighing 21 pounds?

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Famotidine Dosing for a 1-Year-Old Child Weighing 21 Pounds

The recommended dose of famotidine for a 1-year-old child weighing 21 pounds (approximately 9.5 kg) is 1 mg/kg/day divided into 2 doses, which equals approximately 9-10 mg per day or 4.5-5 mg twice daily.

Dosing Guidelines for Famotidine in Infants and Children

Famotidine is an H2-receptor antagonist commonly used to treat gastroesophageal reflux disease (GERD) in pediatric patients. According to pediatric gastroenterology guidelines, the appropriate dosing for famotidine in children is as follows:

  • For children 1-16 years: 1 mg/kg/day divided into 2 doses 1
  • Available in cherry-banana-mint flavored oral suspension for pediatric use 1
  • Maximum daily dose should not exceed 40 mg for children

Weight-Based Calculation

For a 21-pound (9.5 kg) child:

  • Dose = 1 mg/kg/day × 9.5 kg = 9.5 mg/day
  • Divided into two doses = 4.75 mg twice daily (can be rounded to 5 mg twice daily for practical administration)

Administration Considerations

  • Famotidine can be given with or without food
  • For optimal absorption, it's best administered 15-30 minutes before meals
  • The cherry-banana-mint flavored oral suspension formulation is ideal for young children 1

Evidence Supporting This Dosage

Research studies have demonstrated that famotidine at 0.5-1 mg/kg/day is effective for treating GERD in infants and young children 2. A multi-center study found that 0.5 mg/kg may be efficacious, but 1.0 mg/kg may provide better symptom control in some infants 2.

Pharmacokinetic studies show that famotidine clearance in children over 3 months of age is similar to that in older children and adults, supporting the standard pediatric dosing recommendation 3.

Important Considerations

  • Monitor for potential side effects, which may include:

    • Agitation or irritability (most common in infants)
    • Headache (may manifest as head-rubbing in infants)
    • Somnolence
    • Decreased appetite 2
  • Duration of therapy should be limited to the shortest period necessary to control symptoms, as prolonged acid suppression may increase the risk of infections and nutritional deficiencies

  • If symptoms persist despite appropriate dosing, reevaluation of the diagnosis is warranted

Practical Administration Tips

  • Measure liquid medication using a calibrated syringe or medicine cup for accuracy
  • Administer consistently with respect to meals (preferably before meals)
  • If using tablets that need to be split, consider consulting a pharmacist about appropriate compounding options for accurate pediatric dosing

Remember that while famotidine is generally well-tolerated in infants, treatment should focus on addressing the underlying cause of reflux symptoms when possible, including consideration of feeding modifications and positioning strategies in addition to medication.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Pharmacokinetics of famotidine in infants.

Clinical pharmacokinetics, 2005

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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