That's a very good question.  My son was in the hospital with an unexplained
fever at 10 days old and, therefore, received antibiotics while in the
hospital and after returning home.  He had his first ear infection at 2
months - more antibiotics.  His first known milk reaction was at four months.
 Up to that point he had been almost exclusively breastfed, except for the
small amount of formula we had been able to convince him to take from a
bottle.  (I thought he didn't like the bottle, then discovered he didn't like
the formula because he is allergic to it.)  He is not asthmatic, but I have
no idea what role his milk allergy might have played in his illnesses, or the
antibiotics might have played in his allergy.

Sandy