Pepto-bismal vs antiacid

Pepto-bismal and antiacid both are nouns.

Word	Noun	Adjective	Verb	Adverb
Pepto-bismal	Yes	No	No	No
antiacid	Yes	No	No	No

As nouns, antiacid is a hypernym of Pepto-bismal; that is, antiacid is a word with a broader meaning than Pepto-bismal:

Pepto-bismal: an antacid
antiacid: an agent that counteracts or neutralizes acidity (especially in the stomach)

Other hypernyms of Pepto-bismal include alkaliser, alkalizer, antacid, gastric antacid.

Pepto-bismal (noun)	antiacid (noun)
an antacid	an agent that counteracts or neutralizes acidity (especially in the stomach)