A person can become allergic to something/anything at any time in his/her life. It is true that some people are born with allergies, but it is also true that you can be born with no allergies and develop them later in life. For example, I've had three pneumonia vaccines in my life; with the first two, I had no problems, but with the third I developed a severe allergy and cannot have the shot again. The same princicple applies with everything from bee stings, to pollen, to tylenol, and to penicillin. Hope this helps!
at 10:43 AM on Jul. 16, 2009