neuralgia vs neuralgy

neuralgia and neuralgy both are nouns.

Word	Noun	Adjective	Verb	Adverb
neuralgia	Yes	No	No	No
neuralgy	Yes	No	No	No

As nouns, neuralgia and neuralgy are synonyms defined as:

neuralgia and neuralgy: acute spasmodic pain along the course of one or more nerves

neuralgia (noun)	neuralgy (noun)
acute spasmodic pain along the course of one or more nerves	acute spasmodic pain along the course of one or more nerves