What is the recommended amoxyclav (amoxicillin + clavulanic acid) dosage for children, including dose per kilogram, dosing interval, and adjustments for severe infection or impaired renal function?

Amoxicillin-Clavulanate (Amoxyclav) Dosing for Pediatric Patients

For most pediatric infections, prescribe high-dose amoxicillin-clavulanate at 90 mg/kg/day of the amoxicillin component plus 6.4 mg/kg/day of clavulanate, divided into two doses every 12 hours, with a maximum daily dose of 4,000 mg amoxicillin. 1

Standard High-Dose Regimen (Preferred for Most Infections)

The high-dose formulation (90/6.4 mg/kg/day in two divided doses) is the treatment of choice for respiratory tract infections, acute otitis media, and acute bacterial rhinosinusitis in children. 1 This regimen provides:

• Optimal coverage against penicillin-resistant Streptococcus pneumoniae and β-lactamase-producing Haemophilus influenzae and Moraxella catarrhalis 1
• A 14:1 amoxicillin-to-clavulanate ratio that reduces diarrhea incidence compared to other formulations while preserving efficacy 1
• Maximum single dose: 2,000 mg amoxicillin per administration, regardless of weight 1

When High-Dose Therapy Is Mandatory

Use the 90 mg/kg/day regimen when ANY of the following risk factors are present: 1

• Age < 2 years 1
• Daycare attendance 1
• Antibiotic use within the preceding 30 days 1
• Incomplete Hib vaccination (< 3 doses) 1
• Residence in an area where > 10% of S. pneumoniae are penicillin-resistant 1
• Moderate-to-severe illness at presentation 1
• Concurrent purulent acute otitis media 1
• Prior treatment failure with amoxicillin alone 1

Standard-Dose Regimen (Limited Use Only)

• 45 mg/kg/day amoxicillin + 6.4 mg/kg/day clavulanate, divided every 12 hours 1
• Reserved only for uncomplicated infections in children without any identified risk factors 1
• This lower dose is substantially less effective against resistant organisms and should rarely be used 1

Age-Based Suspension Dosing (For Mild Infections Without Risk Factors)

Age	Suspension & Volume (Three Times Daily)
< 1 year (1-12 months)	2.5 mL of 125/31 mg/mL [1]
1-6 years	5 mL of 125/31 mg/mL [1]
7-12 years	5 mL of 250/62 mg/mL [1]
12-18 years	1 tablet (250/125 mg) [1]

Critical caveat: These age-based doses deliver substantially lower amoxicillin exposure than the high-dose regimen and should be reserved only for mild infections without any risk factors 1. Using these doses when high-dose therapy is indicated leads to treatment failure 1.

Infection-Specific Dosing

Acute Otitis Media

• 90 mg/kg/day amoxicillin + clavulanate in two divided doses for 10 days 1
• Predicted clinical efficacy of 90-92% against penicillin-resistant S. pneumoniae 1
• Children < 2 years must receive the high-dose formulation 1

Community-Acquired Pneumonia (Outpatient)

• Children < 5 years: 90 mg/kg/day amoxicillin + clavulanate in two divided doses 1
• If Hib vaccination incomplete or concurrent purulent otitis media: 80-90 mg/kg/day amoxicillin + clavulanate 1
• Duration: 10 days 1
• For children < 3 years without risk factors: Consider amoxicillin alone 80-100 mg/kg/day in three divided doses as first line 1

Acute Bacterial Rhinosinusitis

• 90 mg/kg/day amoxicillin + clavulanate in two divided doses for 10-14 days 1
• Strongly recommended as first-line therapy 1

Skin and Soft-Tissue Infections

• Children < 1 year: 0.266 mL/kg of 125/31 mg/mL suspension three times daily 1
• Duration: 7-10 days, extendable to 14 days based on clinical response 1
• Severe infections: Dose may be doubled 1

Intravenous Dosing for Severe Infections

• 30 mg/kg every 8 hours (three times daily) IV for all pediatric ages 1
• Switch to oral formulation as soon as clinically appropriate 1

Renal Impairment Adjustments

• Prolong the dosing interval according to creatinine clearance to avoid drug accumulation 1
• Both amoxicillin and clavulanate are renally eliminated; significant dose reduction is required in children with reduced renal function 1

Alternatives for Penicillin Allergy

Allergy Type	Recommended Alternative	Typical Dosing
Non-type I (non-anaphylactic)	Clindamycin + third-generation oral cephalosporin	Varies by agent [1]
Type I (anaphylaxis)	Clarithromycin	< 1 yr: 7.5 mg/kg BID; 1-2 yr: 62.5 mg BID; 3-6 yr: 125 mg BID; 7-9 yr: 187.5 mg BID; ≥ 10 yr: 250 mg BID [1]

Monitoring and Expected Clinical Response

• Clinical improvement should occur within 48-72 hours of therapy initiation 1
• If no improvement or worsening after 72 hours: Re-evaluate diagnosis, consider atypical pathogens, assess for complications, or change antibiotics 1
• Continue treatment for an additional 7 days once the child is free of signs and symptoms 1

Common Adverse Effects

• Diarrhea occurs in ~25% of treated children vs 15% with placebo 1
• Nausea, vomiting, and diaper dermatitis occur in ~51% vs 35% with placebo 1
• The 14:1 amoxicillin-to-clavulanate formulation reduces diarrhea incidence compared with other amoxicillin-clavulanate preparations 1

Critical Pitfalls to Avoid

• Underdosing: Using age-based dosing when high-dose therapy is indicated leads to treatment failure against resistant organisms 1
• Subtherapeutic exposure: Fails to achieve adequate serum/tissue levels and promotes resistance 1
• Suspension verification: Always confirm the concentration (125/31 mg/mL vs 250/62 mg/mL) before calculating volume to avoid dosing errors 1
• Abscess management: Primary treatment for fluctuant boils or abscesses is incision and drainage; antibiotics alone are insufficient 1

Minimum Age for Use

• Amoxicillin-clavulanate may be initiated in children ≥ 3 months of age when a bacterial infection is suspected or confirmed 2
• For infants < 3 months with suspected serious bacterial infection, intravenous regimens (e.g., ampicillin + gentamicin or cefotaxime) are preferred over oral amoxicillin-clavulanate 2