atopic allergy vs atopy

atopic allergy and atopy both are nouns.

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

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

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

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

atopic allergy (noun)	atopy (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