As part of the admission procedure in the hospital where I work, I ask the patients if they are allergic to anything. If they are, I print it on an allergy band placed on the patient's wrists.

Once when I asked an elderly woman if she had any allergies, she said she couldn't eat bananas. Imagine my surprise when several hours later a very irate son came out to the nurses' station demanding, "Who's responsible for labeling my mother 'bananas'?"