What is the dosing schedule of Bactrim (trimethoprim/sulfamethoxazole) in pediatric patients?

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From the Guidelines

Bactrim (trimethoprim-sulfamethoxazole) dosing for pediatric patients is typically based on the trimethoprim component at 6-12 mg/kg/day divided into two doses, given every 12 hours, as recommended for infants >2 months of age and children with mild-to-moderate infections 1.

Key Considerations

  • For serious infections, a higher dose of 15-20 mg/kg/day of trimethoprim divided into 3-4 doses may be used 1.
  • Dosing should be adjusted based on the child's weight, with careful consideration in infants under 2 months due to increased risk of kernicterus.
  • The medication is typically given with food to minimize gastrointestinal upset, and adequate hydration should be maintained during treatment.

Monitoring and Adverse Effects

  • Monitoring for adverse effects such as rash, bone marrow suppression, or electrolyte disturbances is important, especially during prolonged therapy.
  • The dual mechanism of trimethoprim and sulfamethoxazole creates a synergistic effect that makes it effective against many common pathogens, by inhibiting two sequential steps in bacterial folate synthesis, with trimethoprim blocking dihydrofolate reductase and sulfamethoxazole inhibiting dihydropteroate synthase.

Special Populations

  • Infants under 2 months require careful consideration due to the increased risk of kernicterus.
  • The standard treatment duration is typically 10-14 days, but may vary depending on the specific infection being treated.

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 following table is a guideline for the attainment of this dosage: Children 2 months of age or older: Weight Dose-every 12 hours lb kg Tablets 22-44 10-20 1 66-88 30-40 2 (400 mg/80 mg) or 1 (DS) tablet

The dosing schedule of Bactrim (trimethoprim/sulfamethoxazole) in pediatric patients is 40 mg/kg sulfamethoxazole and 8 mg/kg trimethoprim per 24 hours, given in two divided doses every 12 hours. The treatment duration is 10 days for urinary tract infections or acute otitis media, and 5 days for shigellosis. 2

From the Research

Dosing Schedule of Bactrim in Pediatric Patients

  • The dosing schedule of Bactrim (trimethoprim/sulfamethoxazole) in pediatric patients can be determined based on the patient's age and weight 3.
  • For pediatric patients, the optimal dosing of trimethoprim/sulfamethoxazole is 8/40 mg/kg of body weight/day divided into administration every 12 hours, which achieves the same exposure as in adults and meets the pharmacodynamic target for efficacy 3.
  • Alternatively, dosing of 12/60 and 15/75 mg/kg/day divided into administration every 12 hours can also be used, depending on the age of the patient and the susceptibility of the bacteria 3.
  • Other studies have used different dosing regimens, such as 8/40 mg/kg/day divided into twice daily administration for the treatment of urinary tract infections in infants and children 4.

Specific Conditions

  • For the prevention of Pneumocystis carinii (jiroveci) pneumonia in pediatric oncology patients, trimethoprim/sulfamethoxazole can be dosed on 2 consecutive days per week 5.
  • For the treatment of urinary tract infections in adolescents, trimethoprim/sulfamethoxazole can be used for 3 days for lower tract infections and 10-14 days for upper tract infections 6.

Considerations

  • The dosing schedule of Bactrim in pediatric patients should be individualized based on the patient's specific condition, age, and weight 3, 6, 4, 5.
  • The susceptibility of the bacteria to trimethoprim/sulfamethoxazole should also be considered when determining the dosing regimen 3, 4.

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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