From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
The maximum dose of amoxicillin is 4 grams daily for severe infections, particularly those affecting the respiratory tract or caused by less susceptible organisms, as supported by the most recent study 1.
Key Considerations
- For adults and children weighing more than 40 kg, the typical maximum daily dose is 3 grams (3000 mg), usually divided into three doses of 1 gram each, taken every 8 hours.
- For children weighing less than 40 kg, the maximum dose is typically 80-90 mg/kg/day divided into two or three doses.
- Exceeding these recommended doses increases the risk of side effects including gastrointestinal disturbances (diarrhea, nausea, vomiting), allergic reactions, and can potentially lead to antibiotic resistance.
Dosing Disparities
- A study published in 2024 1 found that larger children are often prescribed declining doses of amoxicillin in mg/kg/d, resulting in most patients above 60 kg receiving less than 40 mg/kg/d.
- This disparity in dosing may lead to inadequate treatment of infections in older children and highlights the need for careful consideration of weight-based dosing.
Mechanism of Action
- Amoxicillin is a beta-lactam antibiotic that works by inhibiting bacterial cell wall synthesis, and appropriate dosing ensures sufficient drug concentration to effectively kill bacteria while minimizing adverse effects.
Special Considerations
- Patients with kidney impairment may require dose adjustments as amoxicillin is primarily excreted through the kidneys.
- The use of high-dose amoxicillin approaches adult doses, making clinicians reluctant to exceed "adult doses," but the most recent study 1 supports the use of up to 4 grams daily for severe infections.