What is the dose of Bactrim (Trimethoprim/Sulfamethoxazole) for a Staphylococcus aureus abscess in a child weighing 17 kilograms?

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From the Guidelines

For a 17 kg child with a staph abscess, the recommended dose of Bactrim (trimethoprim-sulfamethoxazole) is 8-12 mg/kg/day of the trimethoprim component, divided into two doses, as per the guidelines outlined in the 2014 update by the Infectious Diseases Society of America 1. This translates to approximately 68-102 mg of trimethoprim twice daily. Using the standard pediatric suspension (40 mg trimethoprim/200 mg sulfamethoxazole per 5 mL), this would be about 8.5-12.5 mL twice daily.

Key Considerations

  • The typical duration of treatment is 7-10 days, depending on clinical response, and incision and drainage of the abscess is also an essential component of treatment when fluctuance is present.
  • Bactrim is effective against methicillin-resistant Staphylococcus aureus (MRSA), which is a common cause of skin abscesses, as noted in the guidelines 1.
  • The medication works by inhibiting bacterial folate synthesis at two different points in the pathway, making it bactericidal.
  • Common side effects include gastrointestinal upset and rash, and the medication should be taken with plenty of fluids.
  • Parents should be advised to complete the full course even if symptoms improve before completion.

Alternative Options

  • If the child has a sulfa allergy, alternative antibiotics like clindamycin should be considered, as outlined in the guidelines 1.
  • Clindamycin is a bacteriostatic antibiotic that is effective against MRSA, but it has a potential for cross-resistance and emergence of resistance in erythromycin-resistant strains.

From the FDA Drug Label

Children: The recommended dose for children with urinary tract infections or acute otitis media is 40 mg/kg sulfamethoxazole and 8 mg/kg trimethoprim per 24 hours, given in two divided doses every 12 hours for 10 days.

The dose of Bactrim for a 17 kg child is 40 mg/kg sulfamethoxazole and 8 mg/kg trimethoprim per 24 hours, which translates to:

  • 40 mg/kg x 17 kg = 680 mg sulfamethoxazole per 24 hours
  • 8 mg/kg x 17 kg = 136 mg trimethoprim per 24 hours Given in two divided doses every 12 hours, the dose would be:
  • 340 mg sulfamethoxazole and 68 mg trimethoprim every 12 hours 2

From the Research

Dose of Bactrim for Staph Abscess in a 17 kg Child

  • The provided studies do not directly address the dosage of Bactrim (trimethoprim-sulfamethoxazole) for a staph abscess in a 17 kg child 3, 4, 5, 6, 7.
  • However, the studies discuss the use of trimethoprim-sulfamethoxazole (TMP-SMX) as a treatment option for infections caused by methicillin-resistant Staphylococcus aureus (MRSA) 3, 4, 5, 6.
  • The dosage of TMP-SMX is not specified in the provided studies, but it is mentioned as a viable treatment option for MRSA infections 5.
  • Clindamycin, doxycycline, and minocycline are also discussed as potential treatment options for MRSA infections, but the dosage for a 17 kg child is not provided 3, 4, 6.
  • There is limited data to support the use of these antibiotics for MRSA pneumonia treatment, and randomized controlled trials are required to determine their effectiveness 6.

Treatment Options for Staph Aureus Infections

  • Trimethoprim-sulfamethoxazole (TMP-SMX) is considered a viable treatment option for infections caused by MRSA 5.
  • Clindamycin, doxycycline, and minocycline are also potential treatment options for MRSA infections 3, 4, 6.
  • The choice of antibiotic should be based on the susceptibility results and clinical status of the patient 6, 7.

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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