anaphylactic
/ˌænəfaɪˈlæktɪk/Definitions
1. adjective
causing anaphylaxis, or relating to a severe, sudden allergic reaction.
“After eating the peanuts, she became anaphylactic and broke out in hives.”
2. noun
a severe, sudden allergic reaction.
“She had to rush to the hospital because of an anaphylactic episode.”