What is the recommended dose of amoxicillin-clavulanate (amox-clav) for pediatric patients?

Amoxicillin-Clavulanate Dosing in Pediatric Patients

For most pediatric infections requiring amoxicillin-clavulanate, use the high-dose regimen of 90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate divided into 2 doses (maximum 4000 mg/day amoxicillin), as this provides optimal coverage against resistant organisms while maintaining tolerability. 1

Standard High-Dose Regimen

The high-dose formulation provides a 14:1 ratio of amoxicillin to clavulanate, which is the preferred regimen for most pediatric respiratory and soft tissue infections 1. This translates to:

• 90 mg/kg/day of amoxicillin component divided into 2 doses (every 12 hours) 1
• 6.4 mg/kg/day of clavulanate 1
• Maximum daily dose: 4000 mg amoxicillin 1

The 14:1 ratio formulation causes significantly less diarrhea than other amoxicillin-clavulanate preparations while maintaining full efficacy 1. This is a critical advantage, as diarrhea rates with standard formulations can reach 26-33% 2.

Age-Based Oral Suspension Dosing

For standard infections without high-risk factors, age-based dosing can be used 1:

• Less than 1 year (1-12 months): 2.5 ml of 125/31 suspension three times daily 1
• 1-6 years: 5 ml of 125/31 suspension three times daily 1
• 7-12 years: 5 ml of 250/62 suspension three times daily 1
• 12-18 years: 1 tablet (250/125) three times daily 1

Critical pitfall: Always verify the suspension concentration (125/31 vs 250/62) before calculating volume to avoid dosing errors 1.

Indications for High-Dose Therapy

Use the high-dose regimen (90 mg/kg/day) when any of these risk factors are present 1:

• Age less than 2 years 1
• Daycare attendance 1, 3
• Recent antibiotic use within the previous 30 days 1, 3
• Incomplete Haemophilus influenzae type b vaccination (less than 3 injections) 1
• Geographic area with high prevalence of penicillin-resistant S. pneumoniae (>10%) 1, 3
• Moderate to severe illness 1
• Concurrent purulent acute otitis media 1
• Concurrent conjunctivitis (provides coverage for Moraxella catarrhalis) 3

The high-dose regimen achieves middle ear fluid concentrations adequate to overcome penicillin-resistant S. pneumoniae and demonstrates 90-92% predicted clinical efficacy 1, 3. Using standard doses when high-dose therapy is indicated leads to inevitable treatment failure with resistant organisms 1.

Specific Infection Types

Acute Otitis Media

• High-dose regimen: 90 mg/kg/day divided into 2 doses for 10 days 4, 1
• The American Academy of Otolaryngology-Head and Neck Surgery recommends high-dose amoxicillin-clavulanate as first-line for children with severe AOM, bilateral AOM in children 6-23 months, or those receiving amoxicillin in the previous 30 days 4

Community-Acquired Pneumonia

• Children under 5 years: 90 mg/kg/day in 2 doses for 10 days 1
• Children 5 years and older: 90 mg/kg/day in 2 doses (maximum 4000 mg/day) for 10 days 1
• For children under 3 years without risk factors for resistant organisms, amoxicillin alone at 80-100 mg/kg/day in 3 divided doses is preferred over amoxicillin-clavulanate 1

Acute Bacterial Rhinosinusitis

• High-dose regimen: 90 mg/kg/day divided into 2 doses for 10-14 days 1
• This is strongly recommended as first-line therapy in children with acute bacterial rhinosinusitis 1

Intravenous Dosing for Severe Infections

For severe infections requiring IV therapy, administer 30 mg/kg three times daily (every 8 hours) based on the amoxicillin component 1, 5. Alternative dosing is 100-200 mg/kg/day of the amoxicillin component divided every 6-8 hours 5.

• Administration: IV infusion over 15-30 minutes 5
• Maximum dose: 4000 mg/day of amoxicillin component 5
• Indications: Severe infections, inability to tolerate oral medications, hospitalized patients with complicated infections 5

For complicated intra-abdominal infections specifically, use 200 mg/kg/day of amoxicillin component divided every 6 hours 5.

Treatment Duration and Monitoring

• Standard duration: 10 days for most respiratory infections 1
• Acute bacterial rhinosinusitis: 10-14 days in children 1
• Bacterial pneumonia: 10 days 1
• Clinical improvement should be evident within 48-72 hours 1, 5

If no improvement or worsening occurs after 72 hours: Reassess the diagnosis clinically and radiologically, consider atypical pathogens, evaluate for complications, and consider switching antibiotics 1.

Renal Insufficiency Adjustment

In patients with established renal insufficiency, prolong the dosing interval according to creatinine clearance to avoid accumulation 1. For children with altered renal function, significantly reduce the dose due to renal elimination of both amoxicillin and clavulanic acid 1.

Common Pitfalls to Avoid

• Underdosing is the most critical error: Subtherapeutic doses fail to achieve adequate serum and tissue concentrations, promote antimicrobial resistance, and lead to treatment failure 1
• Using standard doses when high-dose therapy is indicated: This results in 20-25% treatment failure rates when risk factors for resistant organisms are present 3
• Incorrect suspension concentration: Always verify whether you're using 125/31 or 250/62 formulation before calculating volume 1
• Prescribing for viral infections: Most upper respiratory tract infections are viral and do not benefit from antibiotics 1