Dany, Note that in Briggs it says that "...the manufacturer considers the drug incompatible with bf." They also note that the levels are not thought to be sufficiently high after therapeutic doses to affect the infant. This is interesting because most manufacturers consider their drugs incompatible with bf regardless of the drug ("...make a decision regarding bf or taking the drug, taking into account the importance of the drug to the mother..." PDR on everything). Briggs doesn't usually quote the manufacturer, so I wonder what's up. Our dear friend Dr. Tom says in his book that only slight drowsiness in the infant would be a side effect. Personally (professionally), I've seen a lot of moms on Benadryl that were nursing, and the babies did just fine, thank you very much.... Jan B.