What is the dosage of Keflex (cephalexin) for urinary tract infections (UTIs) in children?

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From the Guidelines

The recommended dosage of Keflex (cephalexin) for urinary tract infections (UTIs) in children is 50–100 mg/kg per day in 4 doses. This dosage is based on the most recent and highest quality study available, which was published in the journal Pediatrics in 2011 1. The study provides a guideline for the diagnosis and management of the initial UTI in febrile infants and children 2 to 24 months, and it recommends cephalexin as one of the oral treatment options for UTIs.

Some key points to consider when treating UTIs in children with cephalexin include:

  • The total course of therapy should be 7 to 14 days, with 7 days being the minimal duration selected 1
  • The specific dose should be adjusted based on the child's weight, age, and severity of infection
  • Children should complete the full course of antibiotics even if symptoms improve before finishing the medication
  • Adequate fluid intake should be encouraged during treatment to help flush bacteria from the urinary tract

It's also important to note that cephalexin is effective for UTIs because it's a first-generation cephalosporin antibiotic that works by inhibiting bacterial cell wall synthesis, particularly against common UTI-causing organisms like E. coli. Potential side effects include diarrhea, nausea, and allergic reactions, and parents should contact their healthcare provider if the child develops a rash, severe diarrhea, or if symptoms don't improve within 2-3 days of starting treatment.

From the FDA Drug Label

  1. 5 Genitourinary Tract Infections Cephalexin capsules are indicated for the treatment of genitourinary tract infections, including acute prostatitis, caused by susceptible isolates of Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae.
  2. 2 Pediatric Patients (over 1 year of age) The recommended total daily dose of oral cephalexin capsules for pediatric patients is 25 to 50 mg/kg given in equally divided doses for 7 to 14 days.

The genetic name of Keflex is cephalexin. For UTI dosage in kids, the recommended total daily dose is 25 to 50 mg/kg given in equally divided doses for 7 to 14 days 2.

From the Research

Keflex (Cephalexin) Dosage for UTIs in Children

  • The genetic name for Keflex is cephalexin 3.
  • Cephalexin is useful in the treatment of infections of the genitourinary tract, including urinary tract infections (UTIs) 3, 4.
  • Children may need higher doses per kilogram than those used in treating adults due to their greater body water turnover 3.
  • A study found that a 3-day course of cephalexin, 25-50 mg/kg body weight per day, was effective in treating lower urinary tract infections in children 5.
  • The American Academy of Pediatrics recommends cephalexin as a first-line treatment for uncomplicated UTIs in children, with a dosage of 25-50 mg/kg per day, divided into 2-4 doses 6.

Important Considerations

  • Patients with creatinine clearances less than 30 ml/min require a reduction in cephalexin dosage, which should be proportional to the reduced function 3.
  • Resistance rates to cephalexin were found to be low (9.9%) in a study of urinary samples from children with UTIs in a community setting 7.
  • Urinary tract abnormalities and recurrent UTIs were associated with an increase in antibiotic resistance rates, including resistance to cephalexin 7.

References

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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