From the Guidelines
Keflex (cephalexin) is not the first-line treatment for uncomplicated urinary tract infections (UTIs) due to its inferior efficacy and higher propensity for adverse effects compared to other available therapies. 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 be appropriate in certain settings, but their use should be cautious due to inferior efficacy and more adverse effects. The recommended first-line treatments for uncomplicated UTIs include nitrofurantoin monohydrate/macrocrystals, trimethoprim-sulfamethoxazole, and fosfomycin trometamol, among others.
Some key points to consider when treating UTIs with Keflex include:
- The typical dosage for adults is 500 mg orally every 12 hours or 250 mg orally every 6 hours for 7-14 days, depending on infection severity.
- Keflex works well against many common UTI-causing bacteria, particularly E. coli.
- Patients should complete the entire prescribed course even if symptoms improve before finishing the medication.
- It's essential to drink plenty of water while taking Keflex to help flush bacteria from the urinary tract.
- Common side effects may include diarrhea, nausea, and skin rash.
- Those with penicillin allergies should use caution, as about 10% may experience cross-reactivity with cephalosporins.
However, the use of Keflex for UTIs should be reserved for cases where other recommended agents cannot be used, as stated in the guidelines 1. This is due to the availability of more effective and safer treatment options. If symptoms worsen or don't improve within 2-3 days, patients should contact their healthcare provider to reassess the treatment plan.
From the FDA Drug Label
Genitourinary tract infections, including acute prostatitis, caused by Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae The FDA drug label indicates that Cephalexin is effective for treating uncomplicated urinary tract infections (UTI) caused by susceptible strains of Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae 2.
- Key points:
- Cephalexin is indicated for genitourinary tract infections
- Effective against Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae
- Culture and susceptibility tests should be initiated prior to and during therapy 2
From the Research
Effectiveness of Keflex for UTI
- Keflex (cephalexin) is considered a second-line option for treating uncomplicated urinary tract infections (UTI) 3.
- Studies have shown that cephalexin is effective in treating UTIs, with similar treatment failure rates compared to other antibiotics 4, 5.
- Cephalexin has good urinary penetration and is active against many common uropathogens, including Escherichia coli 6, 7.
Dosage and Administration
- Cephalexin can be administered twice daily or four times daily, with similar treatment outcomes 4, 5.
- A twice-daily dosing strategy may improve patient adherence and decrease costs without compromising effectiveness 4, 5.
Comparison to Other Antibiotics
- Cephalexin has been compared to other antibiotics, such as fluoroquinolones and nitrofurantoin, and has shown similar efficacy in treating UTIs 3, 7.
- Cephalexin may be a useful alternative to fluoroquinolones, which are often associated with resistance and side effects 7.
Special Considerations
- The use of cephalexin for UTIs should be guided by local susceptibility patterns and patient factors, such as allergy history and renal function 3, 6.
- Cephalexin may not be effective against extended-spectrum beta-lactamase (ESBL)-producing organisms, and alternative antibiotics may be necessary in these cases 3, 7.