immediate allergy vs atopic allergy

immediate allergy and atopic allergy both are nouns.

Word	Noun	Adjective	Verb	Adverb
immediate allergy	Yes	No	No	No
atopic allergy	Yes	No	No	No

As nouns, immediate allergy and atopic allergy are synonyms defined as:

immediate allergy and atopic allergy: an allergic reaction that becomes apparent in a sensitized person only minutes after contact

Other synonyms of immediate allergy include atopy, type I allergic reaction.

immediate allergy (noun)	atopic allergy (noun)
an allergic reaction that becomes apparent in a sensitized person only minutes after contact	an allergic reaction that becomes apparent in a sensitized person only minutes after contact