hyperacusis vs hyperacusia

hyperacusis and hyperacusia both are nouns.

Word	Noun	Adjective	Verb	Adverb
hyperacusis	Yes	No	No	No
hyperacusia	Yes	No	No	No

As nouns, hyperacusis and hyperacusia are synonyms defined as:

hyperacusis and hyperacusia: abnormal acuteness of hearing due to increased irritability of the sensory neural mechanism; characterized by intolerance for ordinary sound levels

Other synonyms of hyperacusis include auditory hyperesthesia.

hyperacusis (noun)	hyperacusia (noun)
abnormal acuteness of hearing due to increased irritability of the sensory neural mechanism; characterized by intolerance for ordinary sound levels	abnormal acuteness of hearing due to increased irritability of the sensory neural mechanism; characterized by intolerance for ordinary sound levels