I’m glad you mentioned about the penicillin thing, I too thought I was allergic to it and therefore have denied myself of it for most of my life.
Funny thing, allergies and sensitivities… I was allergic to penicillin, my son was allergic to cyclosporin. We both take those drugs with no problems now. I’m going to speak to a specialist soon about how we can build up a “tolerance” to sulpha if it’s an issue. My sister had a horrible peanut allergy as a child. I caught her sneaking peanut butter as a teen (you know sisters). She somehow just “knew” she had out-grown the allergy, she said. 😉 See? I’m not the only one in the family willing to stick my neck out in the name of science! ha. My parents would have SHOT her, if they’d known she had been doing that for years! 🙂