What Is The Most Serious Type Of Allergic Reaction?

I don't know i think that all of them have the potential to be serious try looking on webmed.org

I would think anaphylactic (spelling?) shock.

I had to have 8 shots (bennedryl,steroids&cortizone)then 2 more shots fours later before leaving the hospital I was there for 6 hours plus I used a nibulizer for breathing and did treatments morning and night at home...plus 2 inhalers...and I swelled all over my body...plus was itchy all over...and I was so weak I had to have help off the couch to go to the restroom...it took 6 weeks to get to myself.

Death.  You can die from analphylatic shock if your airway get blocked and you can't breathe