Promethazine (Phenergan) is used for infants and children, to help
them sleep (ha!), and as premedication for anaesthesia and all sorts
of other things. Codeine is compatible with breastfeeding. Codeine
alone can be used for cough; it is very effective.
I would say that the mother can take this medication and breastfeed.
Jack Newman, MD, FRCPC