Classification and labels

How do food allergies get classified? Do they even need to be classified? Should they be classified as an illness? She isn't sick in the traditional definition. Under law life threatening food allergies are a disability. But is she disabled? No. She can do whatever everyone else can do (besides eating certain foods). Should food allergies be classified as a disease? That doesn't sit well with me either.
It's strange not being able to put a label on your child's condition. Maybe that's it. Maybe the word condition covers it.