From White Coat Rants:
"Penicillin “allergies” are notorious. When I ask the patient what their allergic reaction is, they tell me “My mom just always told me I was allergic. I must have had a reaction when I was a little kid.” That’s it. So what do you do?
I have to blame some physicians for not explaining to the patients that nausea, flushing, diarrhea, and bad tastes in the mouth are NOT allergies. They are adverse reactions."
Is This Patient Allergic to Penicillin? An Evidence-Based Analysis of the Likelihood of Penicillin Allergy. JAMA. 2001;285:2498-2505.
A Picture of a Mutated Mast Cell. The Happy Hospitalist, 02/2008.