Mastitis / breast abscess

Duration of treatment: 10 days

Preferred:

Mild case: flucloxacillin 500mg po qds

Moderate or severe: flucloxacillin 1g iv qds (increase to 2g iv qds for severe infection or in obese patients)

Alternative:

For non-severe and severe penicillin allergy: clarithromycin 500 mg po bd

Consider penicillin allergy assessment and delabelling

MRSA positive patients:

co-trimoxazole* 960mg po bd (iv if NBM)

*Breastfeeding: Discuss with pharmacy. Risk of kernicterus in jaundiced infants and of haemolysis in G6PD-deficient infants (due to sulfamethoxazole).

Additional Information

Advise the woman to continue breastfeeding if possible (including from the affected breast). 

Send a sample of breast milk for microscopy, culture, and antibiotic sensitivity. If breast milk culture results are available, treat with an antibiotic that the organism is sensitive to.

If symptoms fail to settle after 48 hours of antibiotic treatment.

• Send a sample of breast milk for microscopy, culture, and antibiotic sensitivity (if this has not already been done)
• Consult micro/ID for advice

See breast abscess section (below) if suspected breast abscess

Duration of treatment: 10 days

Preferred

co-amoxiclav 625 mg po tds

Alternative

For non-severe and severe penicillin allergy:

clarithromycin 500 mg po bd  PLUS  metronidazole 400 mg po tds

Consider penicillin allergy assessment and delabelling

MRSA positive patients

co-trimoxazole 960mg po bd (iv if NBM)

Additional Information

If symptoms fail to settle after 48 hours of antibiotic treatment. Consult Micro/ID for advice

See breast abscess section (below) if suspected breast abscess

Refer the woman urgently to a general surgeon for:

• Confirmation of the diagnosis (by ultrasound).
• Drainage of the abscess (by ultrasound-guided needle aspiration or surgical drainage).
• Culture of fluid from the abscess (which will be used to guide the choice of antibiotic).

Advise lactating women to continue breastfeeding if possible (including from the affected breast).

National Institute for Health and Care Excellent (NICE). CKS. Mastitis and breast abscess. January 2021. Accessed at Mastitis and breast abscess | Health topics A to Z | CKS | NICE