palliative vs alleviative

palliative is a noun but alleviative is not a noun.

Word	Noun	Adjective	Verb	Adverb
palliative	Yes	Yes	No	No
alleviative	No	Yes	No	No

As adjectives, palliative and alleviative are synonyms defined as:

palliative and alleviative: moderating pain or sorrow by making it easier to bear

Other synonyms of palliative include alleviatory, lenitive, mitigative, mitigatory.

palliative (noun)	alleviative (noun)
remedy that alleviates pain without curing

palliative (adjective)	alleviative (adjective)
moderating pain or sorrow by making it easier to bear	moderating pain or sorrow by making it easier to bear