neuroleptic agent vs neuroleptic drug

neuroleptic agent and neuroleptic drug both are nouns.

Word	Noun	Adjective	Verb	Adverb
neuroleptic agent	Yes	No	No	No
neuroleptic drug	Yes	No	No	No

As nouns, neuroleptic agent and neuroleptic drug are synonyms defined as:

neuroleptic agent and neuroleptic drug: tranquilizer used to treat psychotic conditions when a calming effect is desired

neuroleptic agent (noun)	neuroleptic drug (noun)
tranquilizer used to treat psychotic conditions when a calming effect is desired	tranquilizer used to treat psychotic conditions when a calming effect is desired