What is the dosage of co-amoxiclav (amoxicillin/clavulanic acid) 457mg/5ml suspension in milliliters, to be taken twice daily for a 7-day course?

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Dosing Co-Amoxiclav 457mg/5mL Suspension

The appropriate dose depends on the patient's age and weight, but for most children requiring standard dosing, co-amoxiclav 457mg/5mL (which contains amoxicillin 400mg + clavulanate 57mg per 5mL) is typically given as 5mL twice daily for 7 days.

Standard Pediatric Dosing

The 457mg/5mL formulation is specifically designed for pediatric use and provides a 14:1 ratio of amoxicillin to clavulanate, which minimizes gastrointestinal side effects while maintaining efficacy 1.

Weight-Based Dosing Guidelines

For standard-dose therapy:

  • Children requiring 25 mg/kg/day of amoxicillin component: Give approximately 5mL twice daily (for children weighing 16-20 kg) 1
  • Children requiring higher doses: The volume should be adjusted based on the target dose of 40-45 mg/kg/day of the amoxicillin component in 2 divided doses 1

High-Dose Therapy Considerations

For infections requiring high-dose therapy (such as recurrent otitis media, persistent infections, or suspected resistant organisms):

  • Target dose: 90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day of clavulanate in 2 divided doses 1
  • For a 20 kg child: This would require approximately 11.25mL twice daily
  • Maximum daily dose: 4000 mg of amoxicillin component 1

Clinical Context Matters

The specific indication determines the appropriate dosing:

For acute otitis media or sinusitis with suspected resistant pathogens: High-dose formulations (90/6.4 mg/kg/day) are preferred over standard dosing to overcome penicillin-resistant Streptococcus pneumoniae and β-lactamase-producing organisms 1, 2.

For uncomplicated skin/soft tissue infections or mild respiratory infections: Standard dosing of 25-45 mg/kg/day of the amoxicillin component in 2 divided doses is typically adequate 1.

Important Caveats

  • Twice-daily dosing reduces diarrhea: The 457mg/5mL formulation given twice daily causes significantly less diarrhea compared to three-times-daily regimens, with comparable efficacy 3, 4
  • Absorption variability: Clavulanic acid absorption can vary up to 5-fold between patients, though this doesn't typically affect clinical outcomes 5
  • Take with food: Administration with meals improves gastrointestinal tolerability without compromising absorption 3

Practical Dosing Example

For a typical child weighing 20 kg with acute otitis media:

  • Standard dose: 5mL twice daily for 7 days (provides 40 mg/kg/day amoxicillin)
  • High dose (if treatment failure or resistant organisms suspected): 11.25mL twice daily for 7 days (provides 90 mg/kg/day amoxicillin) 1

The 7-day duration is appropriate for most respiratory tract infections in children 1, 3.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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