Is Flucloxacillin compatible with breastfeeding? Do we have alternatives for Flucloxacillin?


July 2, 2015 (Very Low Risk)

Like most penicillin-type antibiotics, excretion into breast milk is clinically non-significant. No harmful effects have been found among breastfed infants from treated mothers.

Widely used for treatment of Mastitis since it has an effective activity against Staphylococcus.

Be aware of false negative results of microbial cultures done from samples of febrile infants whose mothers are treated with antibiotics. Also, due to imbalance of intestinal flora a diarrheal disease can occur in the breastfed infant.

List of Essential Medicines by WHO 2002: compatible with breastfeeding.


We do not have alternatives for Flucloxacillin since it is relatively safe.

Very Low Risk

Compatible. Not risky for breastfeeding or infant.

Low Risk

Moderately safe. Mild risk possible. Follow up recommended. Read the Comment.

High Risk

Poorly safe. Evaluate carefully. Use a safer alternative. Read the Comment.

Very High Risk

Not recommended. Cessation of breastfeeding or alternative.


  • Floxacillin


  • فلوكلوكساسيلين (Arabic)
  • Флуклоксациллин (Cyrillic)
  • 氟氯西林 (Chinese)
  • フロキサシリン (Japanese)


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