From the Guidelines
Keflex (cephalexin) is not the recommended first-line treatment for moderate growth of Cutibacterium acnes and Staphylococcus epidermidis, as the most recent and highest quality studies suggest that doxycycline and minocycline are more effective for acne treatment 1. For skin and soft tissue infections caused by these bacteria, other antibiotics such as clindamycin, TMP-SMX, or a tetracycline (doxycycline or minocycline) may be considered as empirical therapy pending culture results 1. Some key points to consider:
- C. acnes and S. epidermidis are common skin flora that can cause infections, but the choice of antibiotic should be guided by the severity of the infection and the presence of any underlying conditions.
- The use of systemic antibiotics should be limited to the shortest possible duration, ideally 3-4 months, to minimize the development of bacterial resistance 1.
- Patients should be monitored for adverse events, such as gastrointestinal disturbances, allergic reactions, and photosensitivity, especially when taking antibiotics like doxycycline or minocycline 1.
- Concomitant topical therapy with benzoyl peroxide or a retinoid should be used with systemic antibiotics and for maintenance after completion of systemic antibiotic therapy 1.
From the Research
Effectiveness of Keflex against Cutibacterium acnes and Staphylococcus epidermidis
- Keflex, also known as cephalexin, is a cephalosporin antibiotic that has been shown to be effective against various bacterial infections, including those caused by Staphylococcus species 2.
- However, the effectiveness of Keflex against Cutibacterium acnes (formerly known as Propionibacterium acnes) is not well established, with some studies suggesting that it may not be highly effective against this bacterium 3, 4.
- One study found that cephalexin was not highly effective against Staphylococcus aureus, with only 49.1% of strains being suppressed by the antibiotic at concentrations of 3.13 μg/ml or less 5.
- Another study found that Cutibacterium acnes and Staphylococcus epidermidis were susceptible to human whole saliva, but the effectiveness of Keflex against these bacteria was not evaluated in this study 6.
- In terms of moderate growth of Cutibacterium acnes and Staphylococcus epidermidis, there is limited evidence to suggest that Keflex is effective against these bacteria, and more research is needed to determine its efficacy in this context 3, 4.
Antibiotic Susceptibility of Cutibacterium acnes and Staphylococcus epidermidis
- Cutibacterium acnes and Staphylococcus epidermidis have been shown to be susceptible to various antibiotics, including roxithromycin, erythromycin, clindamycin, and minocycline 3, 4.
- However, resistance to these antibiotics has been reported, particularly among Staphylococcus epidermidis strains 3.
- Cephalexin has been shown to be effective against Staphylococcus species, but its effectiveness against Cutibacterium acnes is not well established 2, 5.