What is the suitable dose of Pepcid (famotidine) for a 7-year-old child weighing 89 pounds?

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Pepcid Dosing for a 7-Year-Old Child Weighing 89 Pounds

For a 7-year-old child weighing 89 pounds (40.4 kg), the appropriate dose of Pepcid (famotidine) is 40 mg per day, divided into two doses of 20 mg twice daily. 1

Weight-Based Dosing Calculation

  • The standard pediatric dosing for famotidine is 1 mg/kg/day divided into 2 doses 1
  • For an 89-pound child (40.4 kg): 1 mg/kg/day × 40.4 kg = 40.4 mg/day 1
  • This translates to approximately 20 mg twice daily (morning and evening) 1

FDA-Approved Age Range

  • Famotidine is FDA-approved for children aged 1 to 16 years 1
  • Your 7-year-old patient falls well within this approved age range 1
  • The medication is available as a cherry-banana-mint flavored oral suspension, which is appropriate for pediatric use 1

Clinical Context and Duration of Action

  • Famotidine begins working within 1 hour of administration and reaches maximum effect in 1-3 hours 2
  • The antisecretory effect lasts approximately 10-12 hours, supporting twice-daily dosing 2
  • In pediatric studies, a single dose maintained gastric pH above 4.0 for approximately 9 hours on average 3, 4

Important Considerations

  • Tachyphylaxis warning: H2-receptor antagonists like famotidine can develop reduced effectiveness within 6 weeks of continuous use 1
  • If symptoms persist beyond 6 weeks or the medication becomes less effective, consider switching to a proton pump inhibitor rather than increasing the famotidine dose 1
  • Monitor for potential side effects, though famotidine is generally well-tolerated in children with minimal adverse effects reported 5
  • The medication should be given with or without food, though administration with food may reduce gastrointestinal side effects if they occur 1

Practical Administration

  • Use the oral suspension formulation for easier administration in a 7-year-old 1
  • Administer 20 mg in the morning and 20 mg in the evening (approximately 12 hours apart) 1
  • No dose adjustment is needed unless the child has significant renal impairment 2

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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