What is the recommended dose of co-amoxiclav (amoxicillin/clavulanic acid) for a patient weighing 30kg?

Co-Amoxiclav Dosing for 30kg Patient

For a 30kg child, the recommended dose of co-amoxiclav depends on the clinical indication: for mild-to-moderate infections use 45 mg/kg/day of amoxicillin component (1350 mg/day total, divided into 675 mg twice daily), while for severe infections, high-risk situations, or suspected resistant organisms use 80-90 mg/kg/day (2400-2700 mg/day total, divided into 1200-1350 mg twice daily). 1

Standard Dosing Framework

Mild-to-Moderate Infections

• Standard dose: 45 mg/kg/day of amoxicillin component in 2 divided doses 1
  • For 30kg patient: 1350 mg/day total = 675 mg twice daily
  • This applies to uncomplicated respiratory infections in children ≥2 years without recent antibiotic exposure 1

High-Dose Regimen Indications

• High-dose: 80-90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses 1
  • For 30kg patient: 2400-2700 mg/day = 1200-1350 mg twice daily
  • Maximum single dose: 2000 mg 1

When to Use High-Dose Regimen

Use high-dose co-amoxiclav (80-90 mg/kg/day) for any of the following: 1

• Age <2 years
• Child care attendance
• Antibiotic use within past 30 days
• Moderate-to-severe illness presentation
• Geographic areas with >10% nonsusceptible S. pneumoniae prevalence
• Suspected β-lactamase-producing organisms (H. influenzae, M. catarrhalis)

Special Clinical Scenarios

Community-Acquired Pneumonia

• For children <3 years with pneumococcal pneumonia: 80-100 mg/kg/day amoxicillin component in 3 divided doses 1
  • For 30kg patient: 2400-3000 mg/day = 800-1000 mg three times daily
  • This higher dosing specifically targets pneumococcal infections 1
  • Duration: 10 days for bacterial pneumonia 1

Acute Bacterial Sinusitis

• Standard dose (45 mg/kg/day) for uncomplicated cases in children ≥2 years 1
• High-dose (80-90 mg/kg/day) for moderate-to-severe illness or risk factors 1
• Duration: Continue for 7 days after symptom resolution, minimum 10 days total 1

Critical Dosing Considerations

Important caveats to avoid common errors:

• The clavulanate component should be 6.4 mg/kg/day for high-dose regimens (not proportionally increased with amoxicillin) 1
• Never substitute two 250 mg tablets for one 500 mg tablet, as this results in excessive clavulanate dosing 2
• Twice-daily dosing improves compliance and reduces diarrhea compared to three-times-daily regimens 3
• For children weighing <30kg, amoxicillin monotherapy (not co-amoxiclav) is preferred for uncomplicated pneumococcal pneumonia unless specific risk factors exist 1

Practical Formulation Selection

For a 30kg patient requiring high-dose therapy:

• Use formulations that provide appropriate amoxicillin:clavulanate ratios (14:1 or higher) 1, 3
• The 600 mg/42.9 mg per 5 mL suspension (ES-600 formulation) provides 90 mg/kg/day amoxicillin with 6.4 mg/kg/day clavulanate when dosed appropriately 3
• Alternatively, use tablet formulations: 875/125 mg tablets can be given as 1.5 tablets twice daily for high-dose regimen