methacholine vs medicinal drug

methacholine and medicinal drug both are nouns.

Word	Noun	Adjective	Verb	Adverb
methacholine	Yes	No	No	No
medicinal drug	Yes	No	No	No

As nouns, medicinal drug is a hypernym of methacholine; that is, medicinal drug is a word with a broader meaning than methacholine:

methacholine: parasympathomimetic drug (trademark Mecholyl) that stimulates secretions and smooth muscle activity
medicinal drug: (medicine) something that treats or prevents or alleviates the symptoms of disease

Other hypernyms of methacholine include medicament, medication, medicine.

methacholine (noun)	medicinal drug (noun)
parasympathomimetic drug (trademark Mecholyl) that stimulates secretions and smooth muscle activity	(medicine) something that treats or prevents or alleviates the symptoms of disease