What is the appropriate dosage of Augmentin (amoxicillin/clavulanic acid) liquid for a patient with a urinary tract infection (UTI) weighing 18.6 kg?

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Augmentin Dosing for Pediatric UTI at 18.6 kg

For a child weighing 18.6 kg with a urinary tract infection, the appropriate dosage of Augmentin (amoxicillin/clavulanic acid) is 45-90 mg/kg/day of the amoxicillin component divided into 2-3 doses, which translates to approximately 375 mg of Augmentin per dose given three times daily.

Dosage Calculation

  • For a child weighing 18.6 kg, the appropriate dosage range is 45-90 mg/kg/day of the amoxicillin component 1
  • This calculates to approximately 837-1,674 mg of amoxicillin per day
  • When divided into three doses, this equals approximately 279-558 mg per dose
  • The standard formulation of Augmentin contains amoxicillin plus clavulanic acid in a fixed ratio 2
  • The appropriate formulation would be Augmentin 375 mg (250 mg amoxicillin + 125 mg clavulanic acid) given three times daily 2, 3

Treatment Duration

  • For uncomplicated UTIs, treatment duration of 3-7 days is generally recommended 1
  • For complicated UTIs, treatment should be extended to 7-14 days 1
  • For male children where prostatitis cannot be excluded, consider extending treatment to 14 days 1

Administration Considerations

  • Augmentin liquid formulation should be given with meals to reduce gastrointestinal side effects 4
  • The medication should be stored in the refrigerator and shaken well before each use
  • Complete the full course of antibiotics even if symptoms improve before completion 1

Monitoring and Follow-up

  • Monitor for clinical improvement within 48-72 hours of initiating treatment 1
  • Consider urine culture follow-up in complicated cases or treatment failures 1
  • Watch for potential side effects including diarrhea, nausea, vomiting, and skin rash 4, 3

Special Considerations

  • If the patient has renal impairment, dosage adjustment may be necessary 5
  • For severe infections or suspected resistant organisms, higher doses within the recommended range should be considered 6
  • If the patient has a history of penicillin allergy, alternative antibiotics should be selected 1

Common Pitfalls to Avoid

  • Underdosing may lead to treatment failure and development of resistance 6
  • Using adult formulations for pediatric patients can lead to dosing errors 1
  • Failure to complete the full course of antibiotics may result in recurrence of infection 1
  • Not considering local resistance patterns when selecting empiric therapy 1

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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