What is the recommended dosage of Cefazolin (Cefazolin) for a child weighing 41 pounds with normal renal function?

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From the Guidelines

For a 41-pound child, the recommended dosage of cefazolin is 75 mg/kg every 8 hours, as stated in the guidelines 1. This translates to approximately 18.6 kg x 75 mg/kg = 1395 mg every 8 hours. To administer this dose, it would be given as 1395 mg every 8 hours, which can be rounded to 1400 mg every 8 hours for simplicity. Some key points to consider when administering cefazolin include:

  • Cefazolin should be administered intravenously or intramuscularly, as it is not available in oral form.
  • The duration of treatment depends on the specific infection being treated, typically ranging from 1-14 days.
  • Cefazolin is a first-generation cephalosporin antibiotic effective against many gram-positive bacteria and some gram-negative organisms.
  • It works by inhibiting bacterial cell wall synthesis.
  • Renal function should be assessed before administration, as dosage adjustments may be necessary in patients with kidney impairment.
  • Monitor for allergic reactions, especially in patients with known penicillin allergies due to potential cross-reactivity. It's also worth noting that the guidelines from 1 provide additional context for the use of cefazolin in various infections, but the dosage recommendation remains consistent with 1.

From the FDA Drug Label

In pediatric patients, a total daily dosage of 25 to 50 mg/kg (approximately 10 to 20 mg/lb) of body weight, divided into 3 or 4 equal doses, is effective for most mild to moderately severe infections. Pediatric Dosage Guide Weight | 25 mg/kg/day Divided into 3 Doses | 25 mg/kg/day Divided into 4 Doses Lbs | Kg | Approximate Single Dose mg/q8h | Vol. (mL) needed with dilution of 125 mg/mL | Approximate Single Dose mg/q6h | Vol. (mL) needed with dilution of125 mg/mL 40 | 18.1 | 150 mg | 1.2 mL | 115 mg | 0.9 mL

For a 41-pound child, the dosage can be calculated as follows:

  • The child's weight is approximately 18.6 kg (since 1 pound is approximately 0.45 kg).
  • Using the recommended dosage of 25 to 50 mg/kg/day, the total daily dosage would be 25 mg/kg/day * 18.6 kg = 465 mg/day for mild to moderate infections.
  • Divided into 3 doses, the approximate single dose would be 465 mg / 3 = 155 mg every 8 hours.
  • Divided into 4 doses, the approximate single dose would be 465 mg / 4 = 116 mg every 6 hours.

Recommended dosage for a 41-pound child:

  • For mild to moderate infections: 155 mg every 8 hours or 116 mg every 6 hours.
  • It is essential to consult with a healthcare professional to determine the appropriate dosage and treatment plan for the specific infection and patient needs 2.

From the Research

Cefazolin Dosage for a 41-Pound Child

  • The provided studies do not directly address the dosage of cefazolin for a 41-pound child.
  • However, the studies discuss the use of cefazolin in treating various infections, including methicillin-susceptible Staphylococcus aureus (MSSA) bloodstream infections 3, 4, 5 and urinary tract infections 6.
  • The dosage of cefazolin is not explicitly stated in the provided studies, but it is mentioned that the mean daily dose of cefazolin was 6.5g/d in a study of patients with MSSA infections 4.
  • Another study compared the use of cefazolin and ceftriaxone in treating MSSA bacteraemia, but it does not provide information on dosage for children 5.
  • A study from 1994 compared the use of cefazolin and ceftriaxone as prophylactic antibiotics in abdominal surgery, but it does not provide information on dosage for children 7.
  • There are no research papers provided that directly assist in determining the dosage of cefazolin for a 41-pound child.

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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