dimenhydrinate vs antihistamine

dimenhydrinate and antihistamine both are nouns.

Word	Noun	Adjective	Verb	Adverb
dimenhydrinate	Yes	No	No	No
antihistamine	Yes	No	No	No

As nouns, antihistamine is a hypernym of dimenhydrinate; that is, antihistamine is a word with a broader meaning than dimenhydrinate:

dimenhydrinate: antihistamine and antiemetic (trade name Dramamine) used to treat motion sickness
antihistamine: a medicine used to treat allergies and hypersensitive reactions and colds; works by counteracting the effects of histamine on a receptor site

Other hypernyms of dimenhydrinate include antiemetic, antiemetic drug.

dimenhydrinate (noun)	antihistamine (noun)
antihistamine and antiemetic (trade name Dramamine) used to treat motion sickness	a medicine used to treat allergies and hypersensitive reactions and colds; works by counteracting the effects of histamine on a receptor site