What is the appropriate weight‑based dosing regimen of Clavulin (amoxicillin‑clavulanate potassium) for children, including adjustments for infection severity, renal impairment, and penicillin allergy?

Clavulin (Amoxicillin-Clavulanate) Dosing for Children

For most pediatric infections, use high-dose amoxicillin-clavulanate at 90 mg/kg/day of the amoxicillin component 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 including penicillin-resistant Streptococcus pneumoniae and β-lactamase-producing Haemophilus influenzae. 1

Standard Weight-Based Dosing Algorithm

High-Dose Regimen (Preferred for Most Infections)

• 90 mg/kg/day amoxicillin with 6.4 mg/kg/day clavulanate in 2 divided doses 1
• This achieves a 14:1 ratio of amoxicillin to clavulanate, which causes less diarrhea than other formulations while maintaining efficacy 1
• Maximum single dose: 2000 mg amoxicillin per dose regardless of weight 1
• Treatment duration: 10 days for most respiratory infections 1

Standard-Dose Regimen (Limited Use)

• 45 mg/kg/day amoxicillin with 6.4 mg/kg/day clavulanate in 2 divided doses 1
• Only appropriate for uncomplicated infections in children without risk factors 2

Age-Based Oral Suspension Dosing

When using fixed-dose suspensions rather than weight-based calculations:

For Standard Infections (Three Times Daily)

• <1 year (1-12 months): 2.5 ml of 125/31 suspension three times daily 3, 1
• 1-6 years: 5 ml of 125/31 suspension three times daily 3, 1
• 7-12 years: 5 ml of 250/62 suspension three times daily 3, 1
• 12-18 years: 1 tablet (250/125) three times daily 3

Critical caveat: These age-based doses provide substantially lower amoxicillin amounts than the recommended high-dose regimen and should only be used for mild infections without risk factors. 1

Indications for High-Dose Therapy

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

• Age <2 years 1, 2
• Daycare attendance 1, 2
• Recent antibiotic use within 30 days 1, 2
• Incomplete Haemophilus influenzae type b vaccination (<3 injections) 1
• Geographic area with high prevalence (>10%) of penicillin-resistant S. pneumoniae 1, 2
• Moderate to severe illness at presentation 1
• Concurrent purulent acute otitis media 1
• Treatment failure with amoxicillin alone 1

Infection-Specific Dosing

Acute Otitis Media

• 90 mg/kg/day in 2 doses for 10 days 1
• High-dose regimen achieves 90-92% predicted clinical efficacy against penicillin-resistant S. pneumoniae 1
• Children under 2 years specifically warrant high-dose formulation 1

Community-Acquired Pneumonia

• Outpatient children <5 years: 90 mg/kg/day in 2 doses 1
• Children with incomplete Hib vaccination or concurrent purulent otitis media: 80-90 mg/kg/day 1
• Treatment duration: 10 days 1
• For children under 3 years without risk factors, consider amoxicillin alone at 80-100 mg/kg/day in 3 divided doses first 1

Acute Bacterial Rhinosinusitis

• 90 mg/kg/day in 2 doses for 10-14 days 1
• This is strongly recommended as first-line therapy in children with ABRS 1

Skin and Soft Tissue Infections

• For children <1 year: 0.266 ml/kg of 125/31 suspension three times daily 4
• Example: For an 11 kg child, approximately 3 ml of 125/31 suspension three times daily 4
• Duration: 7-10 days, may extend to 14 days depending on clinical response 4
• In severe infections, the dose may be doubled 4

Intravenous Dosing for Severe Infections

• 30 mg/kg three times daily IV for all ages 3, 1
• Switch to oral formulation as soon as clinically appropriate 2

Adjustments for Renal Impairment

• Prolong dosing interval according to creatinine clearance to avoid accumulation 1
• Both amoxicillin and clavulanic acid are renally eliminated, requiring significant dose reduction in children with altered renal function 1

Penicillin Allergy Alternatives

For children with penicillin allergy:

• Non-type I allergy: Clindamycin plus a third-generation oral cephalosporin 2
• Type I allergy (anaphylaxis): Clarithromycin as alternative 3
  • <1 year: 7.5 mg/kg twice daily 3
  • 1-2 years: 62.5 mg twice daily 3
  • 3-6 years: 125 mg twice daily 3
  • 7-9 years: 187.5 mg twice daily 3
  • ≥10 years: 250 mg twice daily 3

Monitoring and Reassessment

• Expect clinical improvement within 48-72 hours 1, 2
• If no improvement or worsening after 72 hours: Reassess diagnosis, consider atypical pathogens, evaluate for complications, or switch antibiotics 1, 2
• Continue treatment for 7 days after the patient becomes free of signs and symptoms 1

Common Pitfalls to Avoid

Underdosing Errors

• Using age-based dosing when high-dose therapy is indicated leads to treatment failure with resistant organisms 1
• Subtherapeutic doses fail to achieve adequate serum and tissue concentrations and promote antimicrobial resistance 1
• Always verify suspension concentration (125/31 vs 250/62) before calculating volume to avoid dosing errors 1

Inappropriate Antibiotic Use

• Most upper respiratory tract infections are viral and do not benefit from antibiotics 1
• Before prescribing, ensure the child meets criteria for bacterial infection (persistent symptoms >10 days, severe symptoms, or "double sickening") 1

Adverse Effects Management

• Common adverse effects include diarrhea (25% vs 15% placebo), nausea, vomiting, and diaper dermatitis (51% vs 35% placebo) 1
• The 14:1 ratio high-dose formulation causes less diarrhea than other amoxicillin-clavulanate preparations 1
• Recent research suggests even lower clavulanate concentrations (80 mg/2.85 mg/kg/day) may reduce diaper dermatitis (21% vs 33%) without compromising efficacy 5

Treatment Duration

• Failure to complete the full course may lead to treatment failure and potential resistance 4
• For most pediatric infections, 10 days is the standard duration 1

Abscess Management

• For fluctuant boils or abscesses, incision and drainage is the primary treatment; antibiotics alone are insufficient 4