From the Guidelines
Keflex (Cephalexin) is not the first-line treatment for urinary tract infections (UTIs) due to its inferior efficacy and higher resistance rates compared to other available antibiotics. According to the 2010 update by the Infectious Diseases Society of America and the European Society for Micrology and Infectious Diseases 1, beta-lactam agents, including cephalexin, are less well studied and may have inferior efficacy and more adverse effects compared to other UTI antimicrobials.
The guidelines recommend nitrofurantoin monohydrate/macrocrystals, trimethoprim-sulfamethoxazole, and fosfomycin trometamol as first-line treatments for acute uncomplicated cystitis due to their minimal resistance and propensity for collateral damage 1.
Some key points to consider when treating UTIs include:
- The choice of antibiotic should be based on local resistance rates and the susceptibility of the infecting strain 1
- Completing the full prescribed course of antibiotics is crucial to prevent recurrence and antibiotic resistance
- A urine culture may be recommended before starting antibiotics to confirm the specific bacteria causing the infection and its antibiotic susceptibility
- Common side effects of antibiotics, including Keflex, may include diarrhea, nausea, or allergic reactions
It's essential to consult with a healthcare professional to determine the best course of treatment for a UTI, as they can assess the individual's specific needs and provide guidance on the most effective antibiotic therapy.
From the FDA Drug Label
Genitourinary tract infections, including acute prostatitis, caused by Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae Keflex (Cephalexin) may be effective in treating a Urinary Tract Infection (UTI) if the infection is caused by susceptible strains of Escherichia coli, Proteus mirabilis, or Klebsiella pneumoniae.
- Key considerations:
- The infection must be caused by one of the specified microorganisms.
- Culture and susceptibility tests should be initiated prior to and during therapy to confirm the effectiveness of cephalexin.
- Renal function studies should be performed when indicated. 2
From the Research
Effectiveness of Keflex in Treating UTI
- Keflex, also known as Cephalexin, is a cephalosporin antibiotic that can be used to treat Urinary Tract Infections (UTIs) 3, 4, 5.
- According to a study published in 2004, nitrofurantoin or a cephalosporin, such as Keflex, may be better choices for patients with recurrent lower UTI and/or previous fluoroquinolone use 3.
- A 2022 study found that oral antibiotics with comparatively lower resistance rates included amoxicillin/clavulanate, cefdinir, cefuroxime, and nitrofurantoin, while cephalexin had a notably high resistance rate 4.
- However, a 2023 study found that cephalexin was effective in treating uncomplicated UTIs in females, with no difference in treatment failure observed between twice-daily and four-times-daily dosing 5.
- Another study published in 1975 found that a single dose of cephalexin 125 mg/day was as effective as a single dose of 250 mg/day in the long-term treatment of urinary tract infection 6.
Considerations for Using Keflex
- The choice of antibiotic for UTI treatment should be based on local antibiogram data and patient-specific factors, such as previous antibiotic use and resistance patterns 3, 7, 4.
- Keflex may not be the best choice for patients with UTIs caused by fluoroquinolone-resistant E. coli, as it has a higher resistance rate in these cases 4.
- However, for patients with uncomplicated UTIs, Keflex may be an effective treatment option, especially when used at a twice-daily dosing strategy, which may improve patient adherence 5.