metformin vs antidiabetic

metformin and antidiabetic both are nouns.

Word	Noun	Adjective	Verb	Adverb
metformin	Yes	No	No	No
antidiabetic	Yes	No	No	No

As nouns, antidiabetic is a hypernym of metformin; that is, antidiabetic is a word with a broader meaning than metformin:

metformin: an antidiabetic drug (trade name Glucophage) prescribed to treat type II diabetes
antidiabetic: a drug used to treat diabetes mellitus

Other hypernyms of metformin include antidiabetic drug.

metformin (noun)	antidiabetic (noun)
an antidiabetic drug (trade name Glucophage) prescribed to treat type II diabetes	a drug used to treat diabetes mellitus