Azithromycin in Lactation

Lexicomp	Azithromycin is excreted in low amounts into breastmik. Decreased appetite, diarrhoea, rash and somnolence have been reported to macrolide antibiotics.
Australian Prescriber	Considered safe to use in pregnancy and breastfeeding. However, it may cause diarrhoea in breastfeeding infants
FDA	Only one study (Sorensen, et al.) reported an increased risk of IHPS after maternal macrolide use during breastfeeding. Authors did not state which macrolide the infants were exposed to through milk. Recommendation against breastfeeding would require further information regarding the potential association between nonerythromycin macrolide exposure in-utero or through breast milk and the incidence of infantile hypertrophic pyloric stenosis because at this time, the known benefits of breastfeeding outweigh any theoretical risks.
CDC	Most experts consider the use of short-term azithromycin compatible with breastfeeding.

References:  

1. Lexicomp
2. Australian Prescriber, 2015, Prescribing Azithromycin
3. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4653965/
4. http://wwwnc.cdc.gov/travel/yellowbook/2016/international-travel-with-infants-children/travel-breastfeeding
5. http://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/PediatricAdvisoryCommittee/UCM205334.pdf