Might this be an allergy of the throat? (9)
I believe the answer is:
laryngeal
'of the throat?' is the definition.
(laryngeal means relating to the larynx)
'might this be an allergy' is the wordplay.
'might this be' is an anagram indicator.
'an'+'allergy'='anallergy'
'anallergy' with letters rearranged gives 'LARYNGEAL'.
(Other definitions for laryngeal that I've seen before include "Like part of air passage" , "Relating to the voice box" , "of the vocal organ" , "related to part of throat" , "in throat area" .)