IGHE and response to penicillin: 12 of these were patients that had an allergic reaction to a cephalosporin (2 with non-IgE reported penicillin allergy-previously described reaction; 2 with IgE reported penicillin allergy-previously described reaction; 7 not reporting an allergy to penicillin [2 itchiness in recovery room, 1 rash intraoperatively, 1 rash in recovery room, 2 hives intraoperatively, 1 hypotension following cefazolin]; 1 reported rash to penicillin given ceftriaxone and Flagyl®(Pfizer) and needed Benedryl® 9.5 h later with no reason given).