Can Cephalexin (Keflex) be given thrice daily?

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From the Guidelines

Cephalexin Dosage Frequency

Yes, Cephalexin (Keflex) can be given three times a day.

  • The typical adult dose is 250-500 mg every 6 hours, which translates to three to four times a day, depending on the specific infection being treated 1.
  • For example, for uncomplicated urinary tract infections, 250 mg three times a day for 7-14 days is a common regimen.
  • However, the exact dosage and frequency should be determined by a healthcare provider based on the individual's specific condition and medical history.
  • According to the evidence, Cephalexin can be administered at a dose of 50–100 mg/kg per day in 4 doses for children 1, but for adults, the dosage is typically higher.
  • It's essential to note that the dosage and frequency may vary depending on the specific infection, patient's age, weight, and medical history, as well as local patterns of susceptibility of coliforms to antimicrobial agents 1.
  • Cephalexin is ineffective for treatment of Lyme disease and should not be used for this purpose 1.

From the FDA Drug Label

The usual adult dose is 250 mg every 6 hours For the following infections, a dosage of 500 mg may be administered every 12 hours In severe infections, the dosage may be doubled. The adult dosage ranges from 1 to 4 g daily in divided doses.

The recommended dosing frequency for Cephalexin (Keflex) is every 6 hours or every 12 hours, depending on the infection being treated. There is no direct mention of a thrice daily dosing regimen. However, since the usual adult dose is 250 mg every 6 hours, it can be inferred that Cephalexin can be given thrice daily if the dose is adjusted accordingly, but this is not the standard recommended dosing frequency. 2

From the Research

Cephalexin Dosage Frequency

  • Cephalexin can be administered at different frequencies, including twice or thrice daily, depending on the specific treatment regimen and patient needs 3.
  • A study comparing twice-daily and four-times-daily cephalexin dosing for the treatment of uncomplicated urinary tract infections found no significant difference in treatment failure rates between the two groups 4.
  • Another study suggested that cephalexin can be conveniently administered as 500 mg twice or thrice daily, making it a practical choice for clinicians 3.

Specific Dosage Regimens

  • A 5-day regimen of cephalexin at 0.5 g four times daily was compared to a single 3-g dose of fosfomycin trometamol for the treatment of uncomplicated lower urinary tract infections in women, with similar clinical and microbiological efficacies observed between the two groups 5.
  • Cephalexin given twice a day in the dosage of 1 g has been shown to be effective in the treatment of urinary tract infections, with 18 out of 19 patients remaining bacteria-free after treatment 6.

Clinical Implications

  • The flexibility in cephalexin dosing frequency may improve patient adherence to treatment regimens 4.
  • Cephalexin may be a suitable alternative to other antibiotics, such as fluoroquinolones, for the treatment of uncomplicated lower urinary tract infections 3.

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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