Treatment of Mastitis
Continue breastfeeding or milk expression from the affected breast while initiating conservative management first, reserving antibiotics for cases that fail to improve after 1-2 days or present with severe symptoms. 1, 2
Initial Conservative Management (First-Line for 1-2 Days)
Most mastitis cases are inflammatory rather than infectious, making conservative measures the appropriate initial approach 2:
- Continue breastfeeding or expressing milk from the affected breast - this is essential to prevent milk stasis and is considered an adjunct to all other treatments 1, 3
- Administer NSAIDs for pain and inflammation control 2
- Apply ice to the affected area 2
- Feed the infant directly from the breast rather than pumping when possible 2
- Minimize pumping - excessive pumping can worsen the condition by overstimulating milk production 2
Critical caveat: Discontinuing breastfeeding during mastitis worsens the condition and should never be recommended 1, 3. The infant can safely continue nursing as breast milk from an infected breast poses no risk to the baby 3.
Antibiotic Therapy (If No Improvement After 1-2 Days)
Outpatient Oral Antibiotics
When conservative measures fail, initiate narrow-spectrum antibiotics targeting common skin flora 2:
- Dicloxacillin or cephalexin are preferred first-line agents as they effectively cover Staphylococcus aureus, the most common causative organism 3, 4
- Cloxacillin is an alternative first-line option with minimal transfer to breast milk 4
- Consider obtaining milk cultures to guide antibiotic selection, particularly in cases not responding to initial therapy 2, 4
Inpatient Intravenous Antibiotics
Hospital admission with IV antibiotics is warranted for 2:
- Worsening symptoms despite oral antibiotics
- Concern for sepsis
- Immunocompromised patients
For suspected or confirmed MRSA (increasingly common as a cause of mastitis) 3:
- Vancomycin with appropriate therapeutic monitoring is recommended 1
- Linezolid may be superior for severe cases, particularly with MRSA pneumonia 1
- Daptomycin may be preferred when vancomycin MIC >1 mg/L 1
Management of Breast Abscess
Approximately 10% of mastitis cases progress to abscess formation 1, 3:
- Drainage is required - either by surgical incision or needle aspiration 1, 3
- Ultrasonography should be performed to identify abscesses in immunocompromised patients or those with worsening/recurrent symptoms 2
- Breastfeeding can continue on the affected side as long as the infant's mouth does not contact purulent drainage 1, 3
- Early treatment of mastitis and continued breastfeeding prevent abscess formation 3
What NOT to Do (Common Pitfalls)
These practices are no longer recommended as they may worsen mastitis 2:
- Avoid excessive pumping to "empty the breast"
- Avoid heat application to the breast
- Avoid aggressive breast massage - this causes tissue trauma and overstimulation
- Avoid encouraging overfeeding of the infant
Evidence Limitations
The evidence base for antibiotic therapy in mastitis is weak 5. A Cochrane review found insufficient evidence to confirm or refute antibiotic effectiveness, with only two small trials meeting inclusion criteria 5. However, one study suggested faster symptom clearance with antibiotics, and clinical practice guidelines support their use when conservative measures fail 1, 2.