Cephalexin for Mastitis
Cephalexin is an appropriate first-line antibiotic for lactational mastitis in breastfeeding women, particularly when Staphylococcus aureus is the suspected pathogen. 1
Primary Treatment Recommendation
- Cephalexin (along with dicloxacillin) is specifically recommended as an effective antibiotic against Staphylococcus aureus, the most common causative organism in lactational mastitis. 1
- Treatment should be initiated when clinical mastitis is diagnosed (focal breast tenderness, fever, and malaise) and conservative measures (optimizing breastfeeding technique and complete breast emptying) have not resolved symptoms. 1
- Cephalexin is classified as a first-choice antibiotic for mild skin and soft tissue infections by WHO guidelines, which is relevant given mastitis represents a soft tissue infection. 2
Clinical Context and Pathogen Coverage
- Staphylococcus aureus is the predominant pathogen in lactational mastitis, making anti-staphylococcal coverage essential. 1
- Cephalexin provides appropriate coverage against methicillin-sensitive S. aureus (MSSA), which remains the most common variant in community-acquired mastitis. 1
- As methicillin-resistant S. aureus (MRSA) becomes more prevalent in the community, clinicians should consider alternative antibiotics (such as clindamycin or trimethoprim-sulfamethoxazole) if MRSA is suspected or if initial therapy fails. 1
Treatment Algorithm
When to Use Cephalexin:
- First-line therapy when antibiotics are indicated for mastitis 1
- Patient has no history of severe penicillin/cephalosporin allergy 3
- No clinical suspicion of MRSA (absence of purulent drainage, no known MRSA colonization, no recent hospitalization) 2
When to Consider Alternatives:
- Severe penicillin allergy (anaphylaxis, angioedema, urticaria): use clindamycin instead 3
- Suspected or confirmed MRSA: consider clindamycin, trimethoprim-sulfamethoxazole, or doxycycline 2, 1
- Treatment failure after 48-72 hours: reassess and consider MRSA coverage 1
Important Clinical Considerations
- Continued breastfeeding should be strongly encouraged during mastitis treatment and does not pose risk to the infant. 1
- Early antibiotic treatment combined with continued milk removal helps prevent progression to breast abscess, the most common complication of mastitis. 1
- Optimizing breastfeeding technique, often with lactation consultant assistance, is a critical adjunct to antibiotic therapy. 1
Evidence Quality Caveat
- The evidence base for antibiotic therapy in mastitis is surprisingly limited, with insufficient high-quality randomized controlled trials to definitively confirm effectiveness. 4
- One small trial (n=25) found no significant difference between amoxicillin and cephradine for symptom relief, though both appeared effective. 4
- Despite limited trial evidence, clinical experience and pathogen susceptibility patterns support cephalexin as appropriate empiric therapy. 1