Famotidine Pediatric Dose — Gastrointestinal (H2 Blocker)
Famotidine is a histamine H2-receptor antagonist that reduces gastric acid secretion by competitively inhibiting H2 receptors on parietal cells. In pediatric patients, it is used intravenously for acid suppression in conditions such as stress ulcer prophylaxis, gastroesophageal reflux disease (GERD), and peptic ulcer disease. It is available parenterally as a 10 mg/mL solution for IV administration.
Pediatric Dosing
- IV dose: 0.5 mg/kg/dose IV every 12 hours
- Adult/maximum dose: 20 mg/dose IV BID — do not exceed the adult dose regardless of weight
- Available formulation: 10 mg/mL IV solution; 20 mg tablet (see note on oral agent)
Worked example: For a 20 kg child: 20 kg × 0.5 mg/kg = 10 mg/dose IV every 12 hours (= 1 mL of the 10 mg/mL solution). For a 50 kg adolescent: 50 × 0.5 mg/kg = 25 mg — cap at the adult dose of 20 mg/dose IV BID.
Note: Per institutional practice at CHKD, ranitidine is used as the preferred oral agent; famotidine is designated for IV use in this protocol. Consult your institutional protocol for oral acid-suppression dosing.
Indications and Clinical Context
Famotidine IV is indicated in pediatric patients requiring parenteral acid suppression, including stress ulcer prophylaxis in critically ill or post-operative patients, management of GERD when the enteral route is unavailable, and treatment of peptic ulcer disease. H2-receptor antagonists are a standard component of gastrointestinal pharmacotherapy in inpatient pediatric and PICU settings and are generally preferred over antacids when consistent, quantifiable acid suppression is needed via the IV route.
The every-12-hour dosing interval reflects famotidine’s prolonged duration of action compared to other H2 blockers, making it a practical choice for inpatient dosing schedules. Clinical reassessment for transition to oral therapy should occur as soon as the enteral route is established.
Administration and Monitoring
Famotidine should be administered via the intravenous (IV) route for this indication, typically as a slow IV push over at least 2 minutes or as an IV piggyback infusion diluted in normal saline or D5W, per institutional pharmacy guidance. The 10 mg/mL solution should be diluted prior to administration. Monitor for headache, dizziness, and, rarely, QT prolongation, particularly in patients with renal impairment or those on other QT-prolonging agents.
- Reduce dose or extend interval in patients with significant renal impairment (consult institutional protocol)
- Do not exceed 20 mg/dose regardless of calculated weight-based dose
- For oral acid suppression at this institution, transition to ranitidine per local protocol
- Routine monitoring: gastric pH or clinical signs of GI bleeding where applicable
Disclaimer: This article is an educational reference summarizing standard pediatric dosing values. It is not a substitute for clinical judgment. Always verify doses against institutional protocols, the current edition of authoritative references (e.g., Lexicomp, Harriet Lane Handbook, PALS guidelines), the patient’s accurate weight, and any patient-specific factors (renal/hepatic function, allergies, comedications) before administration.