What is the oral dose of amoxicillin (amoxicillin) for a 15-year-old female patient weighing 87 kilograms with acute otitis media and streptococcal pharyngitis?

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From the Guidelines

For a 15-year-old female weighing 87kg with acute otitis media or strep pharyngitis, the recommended oral dose of amoxicillin is 50mg/kg once daily, which translates to approximately 4350mg per day, but given the maximum dose is 1000mg, a more appropriate dose would be 1000mg taken twice daily (every 12 hours) for 10 days, as recommended by the IDSA guideline for managing group A streptococcal pharyngitis 1. The medication should be taken with food to reduce stomach upset. For strep pharyngitis specifically, it's essential to complete the full 10-day course even if symptoms improve earlier to prevent rheumatic fever. For acute otitis media, a 5-7 day course may be sufficient in some cases, but 10 days is often recommended for complete eradication of the infection. If the patient has a penicillin allergy, alternative antibiotics like azithromycin or clindamycin should be considered, as outlined in the clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 update by the Infectious Diseases Society of America 1. Amoxicillin is effective against the common bacterial pathogens in these conditions, including Streptococcus pneumoniae, Haemophilus influenzae, and Group A Streptococcus, by inhibiting bacterial cell wall synthesis. The patient should be advised to drink plenty of fluids while taking the medication. It is crucial to note that the diagnosis of GAS pharyngitis should be established accurately to prevent inappropriate administration of antimicrobials to large numbers of patients with nonstreptococcal pharyngitis, as emphasized in the IDSA guideline 1. In addition to acute disease, streptococcal pharyngitis is important because it can lead to the nonsuppurative postinfectious disorders of acute rheumatic fever with and without carditis, as well as to poststreptococcal glomerulonephritis, highlighting the importance of proper treatment and management 1.

From the Research

Oral Dose of Amoxicillin for Acute Otitis Media and Strep Pharyngitis

  • The recommended oral dose of amoxicillin for a 15-year-old female weighing 87kg with acute otitis media and strep pharyngitis is not explicitly stated in the provided studies.
  • However, according to the study 2, the recommended dosage of amoxicillin for treating acute otitis media is 80-90 mg/kg per day.
  • For a patient weighing 87kg, the calculated dose would be:
    • 80 mg/kg per day: 87kg x 80 mg/kg = 6960 mg per day
    • 90 mg/kg per day: 87kg x 90 mg/kg = 7830 mg per day
  • The study 3 suggests that standard-dose amoxicillin (35-45 mg/kg per day) may be sufficient for treating uncomplicated acute otitis media, but high-dose amoxicillin (80-90 mg/kg per day) may be necessary for patients at high risk of infection with nonsusceptible Streptococcus pneumoniae.
  • The study 4 recommends penicillin or amoxicillin as appropriate treatments for group A streptococcal pharyngitis, but does not specify a dosage.
  • The study 5 compares different antibiotic treatments for group A streptococcal pharyngitis, including amoxicillin, but does not provide dosage information.
  • The study 6 discusses the efficacy of amoxicillin-clavulanate in treating acute otitis media, but does not provide dosage information for amoxicillin alone.

Considerations for Dosage

  • The dosage of amoxicillin should be determined based on the patient's weight and the severity of the infection.
  • The patient's age, medical history, and other factors should also be considered when determining the appropriate dosage.
  • It is essential to consult with a healthcare professional to determine the most effective and safe treatment plan for the patient.

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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