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


June 30, 2015 (Very Low Risk)

Excretion into breast milk is not significant and no side effects on breastfed infants of treated mothers have been shown.

Approved for use as treatment on infants younger than a one year old.

A low oral bioavailability would protect the infant, except in the neonatal period or cases of prematurity. Calcium contained in the milk prevents it from absorption by the gut.

Be aware of the possibility of false negative results of bacterial cultures on febrile infants when the mother is on antibiotics.


We do not have alternatives for Fosfomycin 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.


  • فوسفوميسين (Arabic)
  • Фосфомицин (Cyrillic)
  • 磷霉素 (Chinese)
  • ホスホマイシン (Japanese)


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  3. AEMPS Fosfomicina Ficha técnica 2003 Full text (in our servers)
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