Yes, epi pen is sulfited, but it can stop a reaction to something else long enough to get to a hospital where one can get treated. Actually, they come in 2-packs, and it usually takes both of them to last long enough to get rescued.
IVs don't all contain sulfites. There's no preservative in a saline bag. Frozen veggies don't have sulfites unless they contain onions or garlic or sauces. Frozen juices are clean too, although bottled non-frozen lemon and lime juice are heavily sulfited.
Eating in an Italian restaurant is chancy because they use a lot of garlic. I have to avoid them too.
Bakeries today often buy their products frozen. If they cook from scratch you can ask if they use "dough conditioners" which do contain sulfites. Deli meats contain caramel color, which is sulfited, but it's OK in moeration if you only have the mild sensitivity. Yellow #5 is even worse than red. The Lake colors are OK. Rice vinegar is clean. Unsulfured molasses is OK for most people.
For more complete lists there are many good websites. Ignore the ones that just post copies.www.learningtarget.com/nosulfites/index.htm
is a good place to start.