What is the appropriate dosing of Amoxicillin-Clavulanate (Amoxyclav) based on patient weight?

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From the Guidelines

Amoxicillin-Clavulanate (Amoxyclav) dosing should be weight-based, with a standard pediatric dose of 80-90 mg/kg/day of the amoxicillin component, divided into two doses, for severe infections, as recommended by the most recent guidelines 1.

Key Considerations

  • The dosing is based on the amoxicillin component, not the total weight of the medication.
  • For children, precise calculation is important to avoid under or overdosing.
  • Amoxyclav should be taken with food to reduce gastrointestinal side effects and improve clavulanate absorption.
  • The duration of treatment typically ranges from 7-14 days depending on the infection being treated.

Weight-Based Dosing

  • For children aged 2 years or older with uncomplicated acute bacterial sinusitis that is mild to moderate in degree of severity, amoxicillin is recommended at a standard dose of 45 mg/kg per day in 2 divided doses 1.
  • In communities with a high prevalence of nonsusceptible S pneumoniae (>10%, including intermediate- and high-level resistance), treatment may be initiated at 80 to 90 mg/kg per day in 2 divided doses, with a maximum of 2 g per dose 1.

Special Considerations

  • Patients presenting with moderate to severe illness as well as those younger than 2 years, attending child care, or who have recently been treated with an antimicrobial may receive high-dose amoxicillin-clavulanate (80–90 mg/kg per day of the amoxicillin component with 6.4 mg/kg per day of clavulanate in 2 divided doses with a maximum of 2 g per dose) 1.
  • A single 50-mg/kg dose of ceftriaxone can be used for children who are vomiting, unable to tolerate oral medication, or unlikely to be adherent to the initial doses of antibiotic 1.

From the FDA Drug Label

Table 1 Recommended Dosage for Pediatric Patients Aged 3 Months and Older and Weight Less than 40 kg Ear/Nose/Throat Mild/ Moderate 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours Severe 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours Lower Respiratory Tract Mild/ Moderate or Severe 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours

The appropriate dosing of Amoxicillin-Clavulanate (Amoxyclav) based on patient weight is as follows:

  • For pediatric patients aged 3 months and older and weight less than 40 kg:
    • Mild/Moderate infections: 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours
    • Severe infections: 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours
  • For pediatric patients aged less than 12 weeks (3 months): 30 mg/kg/day divided every 12 hours 2

From the Research

Dosing of Amoxicillin-Clavulanate Based on Patient Weight

The dosing of Amoxicillin-Clavulanate (Amoxyclav) is based on patient weight, with various studies suggesting different dosing regimens.

  • For pediatric patients, a study 3 suggests that a high-dose formulation of amoxicillin/clavulanic acid (90/6.4 mg/kg/day in two divided doses) is effective in treating acute otitis media caused by penicillin-intermediate and -resistant S. pneumoniae.
  • Another study 4 compares the pharmacokinetics of amoxicillin given twice or three times per day to children older than 3 months with pneumonia, and suggests that a 30- to 40-mg/kg/dose b.i.d. regimen may be more effective than the standard 25 mg/kg/dose b.i.d. regimen.
  • A study 5 on critically ill children suggests that four-hourly dosing of 25 mg/kg may be required to achieve therapeutic targets for both amoxicillin and clavulanic acid, and that patients with augmented renal function may require a 1-h infusion instead of bolus dosing.
  • An experimental study 6 on respiratory tract infections caused by strains of Streptococcus pneumoniae suggests that increasing the pediatric amoxicillin unit dose to 90 mg/kg/day while maintaining the clavulanate unit dose at 6.4 mg/kg/day may improve efficacy against penicillin-resistant strains.

Specific Dosing Regimens

Some specific dosing regimens mentioned in the studies include:

  • 40/10 mg/kg/day in three divided doses 3
  • 90/6.4 mg/kg/day in two divided doses 3, 6
  • 25 mg/kg/dose b.i.d. 4
  • 30- to 40-mg/kg/dose b.i.d. 4
  • 25 mg/kg four-hourly 5

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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