A 3-year-old child (~12–15 kg) ingested 25 mL of amoxicillin‑clavulanate suspension (400 mg amoxicillin/5 mL, 57 mg clavulanate/5 mL). What is the recommended management?

Management of Amoxicillin-Clavulanate Overdose in a 3-Year-Old

This child ingested approximately 2,000 mg of amoxicillin (equivalent to ~133–167 mg/kg for a 12–15 kg child), which is a significant overdose but does not require aggressive intervention beyond observation and supportive care. 1

Immediate Assessment and Risk Stratification

No specific antidote or decontamination is indicated for this ingestion. The child ingested 25 mL of a 400 mg/5 mL suspension, delivering 2,000 mg of amoxicillin and 285 mg of clavulanate. For a typical 3-year-old weighing 12–15 kg, this represents approximately 133–167 mg/kg of amoxicillin—well below the doses associated with serious toxicity. 1

• Activated charcoal is not recommended unless the child presents within 1 hour of ingestion and the dose exceeds 200 mg/kg. Even in that scenario, the benefit is marginal because amoxicillin overdose rarely causes serious adverse effects. 1
• In a retrospective study of 15 pediatric amoxicillin overdoses (median dose 219 mg/kg), all patients remained asymptomatic despite significantly exceeding therapeutic doses, and activated charcoal was administered to only 33% of cases with no difference in outcomes. 1

Expected Clinical Course

The child will almost certainly remain asymptomatic. 1

• All 15 patients in the largest pediatric amoxicillin overdose case series remained asymptomatic with normal physical examinations, despite a median ingested dose of 219 mg/kg (range up to 367 mg/kg). 1
• The median time to emergency department presentation in that cohort was 2.1 hours, and no patient developed adverse effects during observation or after discharge. 1

Observation and Monitoring Protocol

Observe the child for 4–6 hours in the emergency department or at home with reliable caregiver instructions. 1

• Monitor for gastrointestinal symptoms (nausea, vomiting, diarrhea), which are the most common adverse effects of therapeutic-dose amoxicillin-clavulanate but remain rare even in overdose. 2, 3
• No laboratory testing is required unless the child develops symptoms. In the overdose case series, blood tests were performed in 47% of patients and urinalysis in 13%, all with normal results. 1
• Renal function monitoring is unnecessary in a previously healthy child with a single acute overdose, as both amoxicillin and clavulanate are renally eliminated but do not cause acute kidney injury at these doses. 4

Discharge Instructions and Follow-Up

Discharge the child home after a brief observation period if asymptomatic. 1

• All 15 patients in the overdose case series were discharged home without complications. 1
• Instruct caregivers to watch for delayed gastrointestinal symptoms (diarrhea, abdominal pain) over the next 24–48 hours, though these are unlikely. 2, 3
• If the child was taking amoxicillin-clavulanate for an active infection, discontinue the current course and reassess the need for continued antibiotic therapy. In the case series, 73% of overdoses required withdrawal of the antibiotic. 1

Pharmacokinetic Context

The ingested dose, while excessive, does not approach toxic thresholds based on pediatric pharmacokinetic data. 5, 6, 7

• Therapeutic high-dose amoxicillin-clavulanate for resistant infections is 90 mg/kg/day (45 mg/kg per dose twice daily), and this single 133–167 mg/kg dose is only 3–4 times the therapeutic single dose. 2, 8
• Peak serum concentrations after therapeutic dosing (9–12 mg/kg) reach 3.5–7.2 mg/L for amoxicillin and 1.2–2.0 mg/L for clavulanate, with terminal half-lives of 1.2–1.4 hours for amoxicillin and 0.8–1.0 hours for clavulanate. 5, 6, 7
• Even at this overdose level, serum concentrations will peak within 1–2 hours and decline rapidly, with complete elimination expected within 8–12 hours. 5, 7

Common Pitfalls to Avoid

• Do not administer activated charcoal routinely. It was given to only 33% of overdose cases in the literature, with no demonstrated benefit, and carries its own risks (aspiration, vomiting). 1
• Do not perform unnecessary laboratory testing. Blood work and urinalysis added no diagnostic or prognostic value in documented overdose cases. 1
• Do not admit the child for observation. All documented pediatric amoxicillin overdoses were safely managed with outpatient observation. 1
• Do not confuse this scenario with chronic supratherapeutic dosing, which can lead to crystalluria or interstitial nephritis—neither of which occurs with a single acute ingestion. 4