From the Guidelines
For a 115-pound (approximately 52 kg) boy with a dirty fish hook puncture wound, the recommended dose of Keflex (cephalexin) is 20 mg per kg per dose twice daily, which translates to approximately 1040 mg per day, or 520 mg taken by mouth every 12 hours. This dosage is based on the guidelines for patients with penicillin allergy, as stated in the study by the Infectious Diseases Society of America 1. The medication should be taken with food to reduce stomach upset. It's essential to complete the full course of antibiotics even if symptoms improve before finishing. The wound should also be thoroughly cleaned with soap and water, and tetanus prophylaxis should be considered if the child's immunizations aren't up to date. Keflex is appropriate for this type of wound because it provides good coverage against common skin bacteria including Staphylococcus and Streptococcus species that might contaminate a puncture wound from a fish hook. If the wound shows signs of worsening infection (increasing redness, warmth, swelling, pus, fever, or red streaking from the wound), medical attention should be sought immediately as a different antibiotic or additional treatment may be needed. Some key points to consider when treating skin and soft tissue infections include the use of antibiotics that cover Staphylococcus and Streptococcus species, as well as the potential need for tetanus prophylaxis and wound cleaning, as recommended by the Infectious Diseases Society of America guidelines 1. Additionally, the World Health Organization's essential medicines list recommends cefalexin as a first-choice antibiotic for skin and soft tissue infections 1. Overall, the recommended dose of Keflex for a dirty fish hook puncture wound in a 115-pound boy is 520 mg taken by mouth every 12 hours, with consideration of wound cleaning, tetanus prophylaxis, and potential signs of worsening infection.
From the FDA Drug Label
Pediatric Patients The usual recommended daily dosage for pediatric patients is 25 to 50 mg/kg in divided doses For streptococcal pharyngitis in patients over 1 year of age and for skin and skin structure infections, the total daily dose may be divided and administered every 12 hours. In severe infections, the dosage may be doubled.
For a 115-pound boy, the dose would be calculated as follows:
- Weight in kg: 115 pounds / 2.2 pounds/kg = 52.3 kg
- Recommended daily dose: 25 to 50 mg/kg
- Total daily dose: 52.3 kg * 25 mg/kg = 1307.5 mg (lower end of range) to 52.3 kg * 50 mg/kg = 2615 mg (upper end of range)
- Divided doses: The total daily dose may be divided and administered every 12 hours for skin and skin structure infections.
Given the context of a dirty fish hook puncture wound, which can be considered a severe infection, the dosage may be doubled, but this would need to be determined by a healthcare provider based on the severity of the infection and the patient's overall condition. The dose could range from 1307.5 mg to 5230 mg per day, divided into 2-4 doses, but the exact dose should be determined by a healthcare professional. 2
From the Research
Recommended Dose of Keflex for a Dirty Fish Hook Puncture Wound
The recommended dose of Keflex (cefalexin) for a dirty fish hook puncture wound in a 115-pound boy is not directly stated in the provided studies. However, we can look at the general guidelines for cephalexin dosage:
- The usual dose of cephalexin for skin and skin structure infections is 250 mg every 6 hours 3.
- For uncomplicated skin and skin structure infections, cephalexin can be given at a dose of 250 mg four times daily 3.
- There is no specific study that recommends a dose of cephalexin for a dirty fish hook puncture wound in a 115-pound boy.
Considerations for Treatment
When considering treatment for a dirty fish hook puncture wound, the following points should be taken into account:
- A study on fishhook injuries suggests that post-removal wound care, including oral antibiotic therapy, may not be critical 4.
- Routine systemic antibiotic prophylaxis is not necessary for uncomplicated soft tissue injury due to fishhooks not involving cartilage or tendons 4.
- Cephalexin has been shown to be effective in treating skin and skin structure infections, including those caused by methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) [(3,5)].
Dosage Guidelines
Based on the available information, the dosage of cephalexin for a 115-pound boy with a dirty fish hook puncture wound could be: