Information from one maternal-infant pair with ivacaftor and lumacaftor indicates that maternal ivacaftor therapy produce low levels in milk. An international survey of cystic fibrosis centers found no adverse effects in breastfed infants of mothers taking these drugs. A task force respiratory experts from Europe, Australia and New Zealand found that these drugs are probably safe during breastfeeding.[1] One breastfed infant had transient elevations in bilirubin and liver enzymes during maternal therapy that could not definitively be attributed to the drugs in breastmilk. Until more data are available, monitoring of infant bilirubin and liver enzymes might be advisable during breastfeeding with maternal lumacaftor and ivacaftor therapy.[2] Congenital cataracts in breastfed infants has been reported in the infants of mothers who took ivacaftor during pregnancy. Examination of breastfed infants for cataracts has been recommended.[3] Anecdotal evidence indicates that the drugs in breastmilk may moderate cystic fibrosis in breastfed infants.