Periactin vs antihistamine

Periactin and antihistamine both are nouns.

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

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

Periactin: an antihistamine (trade name Periactin) used to treat some allergic reactions
antihistamine: a medicine used to treat allergies and hypersensitive reactions and colds; works by counteracting the effects of histamine on a receptor site

Periactin (noun)	antihistamine (noun)
an antihistamine (trade name Periactin) used to treat some allergic reactions	a medicine used to treat allergies and hypersensitive reactions and colds; works by counteracting the effects of histamine on a receptor site