What is the recommended dosage of Augmentin (amoxicillin-clavulanate) for a 14-year-old patient?

Augmentin Dosing for a 14-Year-Old

For a 14-year-old patient, Augmentin dosing depends on weight: if the patient weighs ≥40 kg, use adult dosing of 875 mg/125 mg twice daily or 500 mg/125 mg every 8 hours; if <40 kg, use 45 mg/kg/day of the amoxicillin component divided every 12 hours or 40 mg/kg/day divided every 8 hours for severe infections. 1

Weight-Based Dosing Algorithm

For patients ≥40 kg (88 lbs):

• Mild to moderate infections: 500 mg every 12 hours or 250 mg every 8 hours 1
• Severe infections or lower respiratory tract infections: 875 mg every 12 hours or 500 mg every 8 hours 1
• Maximum daily dose: 4000 mg of amoxicillin component 2

For patients <40 kg:

• Mild to moderate infections: 25 mg/kg/day divided every 12 hours or 20 mg/kg/day divided every 8 hours 1
• Severe infections: 45 mg/kg/day divided every 12 hours or 40 mg/kg/day divided every 8 hours 1
• Maximum daily dose: 4000 mg of amoxicillin component 2

Administration Guidelines

• Take at the start of meals to minimize gastrointestinal intolerance 1
• Continue treatment for a minimum of 48-72 hours beyond symptom resolution or evidence of bacterial eradication 1
• For Streptococcus pyogenes infections, treat for at least 10 days to prevent acute rheumatic fever 1

Renal Impairment Considerations

Important caveat: If the patient has severe renal impairment (GFR <30 mL/min), do NOT use the 875 mg dose 1

• GFR 10-30 mL/min: 500 mg or 250 mg every 12 hours 1
• GFR <10 mL/min: 500 mg or 250 mg every 24 hours 1

Common Clinical Scenarios

For skin and soft tissue infections:

• Use 875 mg/125 mg twice daily (if ≥40 kg) for methicillin-susceptible Staphylococcus aureus 2
• Alternative: 25 mg/kg/day of amoxicillin component in 2 divided doses (if <40 kg) 2

For respiratory tract infections:

• Standard dosing is 875 mg/125 mg twice daily for 10-14 days in adolescents ≥40 kg 3
• For suspected resistant organisms, consider high-dose regimen of 90 mg/kg of amoxicillin component (not exceeding 2 g every 12 hours) 3

For H. influenzae infections:

• Use amoxicillin component at 45-90 mg/kg/day in 2 doses if β-lactamase producing 2

Critical Pitfalls to Avoid

• Never use the 875 mg tablet in patients <40 kg as it cannot be accurately dosed by weight 1
• Do not use 875 mg dose in severe renal impairment (GFR <30 mL/min) due to risk of toxicity 1
• Ensure adequate hydration and monitor for gastrointestinal side effects, which are the most common adverse events 4
• For infections requiring longer therapy (osteomyelitis, endocarditis), treatment may need to continue for several weeks with ongoing clinical follow-up 1