Was not allergic to penicillin as a kid. then when i was 9 showed allergy to pen/cephalo can you outgrow this or am i still allergic?

Maybe,maybe not : Many people break out in rashes during illness and if started on an antibiotic, the antibiotic may be be assumed to have caused the reaction. This may not be a true allergy.Yet people do acquire allergic reactions to new things as they get older, and it could be real. Blood tests can reveal if it is a true allergy which would likely persist over time vs a non allergic reaction that may not be real.