Amoxicillin Pediatric Dose — Antimicrobial Reference
Amoxicillin is a broad-spectrum aminopenicillin antibiotic that inhibits bacterial cell wall synthesis by binding penicillin-binding proteins. It is one of the most widely used oral antimicrobials in pediatrics, indicated for a range of common infections including otitis media, pharyngitis, pneumonia, and urinary tract infections. Its favorable oral bioavailability, palatability, and safety profile make it a first-line agent across all pediatric age groups.
Pediatric Dosing
| Age / Indication | Dose | Frequency | Route |
|---|---|---|---|
| Under 3 months | 10–15 mg/kg/dose | BID | PO |
| Over 3 months (general) | 15–25 mg/kg/dose | BID | PO |
| Acute Otitis Media (AOM) | 40–45 mg/kg/dose | BID | PO |
Maximum dose: 875 mg/dose regardless of weight or indication.
Worked examples: For a 6 kg infant (<3 months): 6 × 10–15 mg/kg = 60–90 mg per dose BID. For a 20 kg child (>3 months, AOM): 20 × 40–45 mg/kg = 800–900 mg per dose — cap at 875 mg/dose. Consult institutional protocol for duration of therapy.
Indications and Clinical Context
Amoxicillin is a first-line oral antimicrobial for community-acquired infections caused by susceptible gram-positive and gram-negative organisms. In children over 3 months, standard dosing addresses uncomplicated infections such as streptococcal pharyngitis and mild community-acquired pneumonia. The higher AOM dosing regimen (40–45 mg/kg/dose BID) is consistent with AAP guidelines and is designed to achieve pharmacodynamic targets against Streptococcus pneumoniae, including strains with intermediate penicillin resistance, in middle-ear fluid.
In neonates and young infants under 3 months, reduced dosing reflects immature renal clearance and altered volume of distribution; use in this age group should be guided by clinical indication and the prescribing clinician’s judgment regarding likely pathogens.
Administration and Monitoring
Amoxicillin is administered orally as a suspension, chewable tablet, or capsule depending on age and weight. Suspensions should be shaken well before each use and stored per manufacturer instructions. The drug may be given without regard to meals, which supports adherence in young children.
- Route: Oral (PO) only per this dosing reference; IV formulations exist but are outside the scope of this description.
- Max single dose: 875 mg — do not exceed regardless of calculated per-kg dose.
- Adverse effects to monitor: Hypersensitivity reactions (rash, urticaria, anaphylaxis), diarrhea, and candidal superinfection with prolonged courses.
- Contraindications: Known hypersensitivity to penicillins or cephalosporins (cross-reactivity); use with caution in patients with a history of severe allergic reactions.
- For resistant organisms or treatment failure, consult institutional antimicrobial stewardship guidelines.
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.