ethical drug vs medicinal drug

ethical drug and medicinal drug both are nouns.

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

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

ethical drug: a drug that is available only with written instructions from a doctor or dentist to a pharmacist
medicinal drug: (medicine) something that treats or prevents or alleviates the symptoms of disease

Other hypernyms of ethical drug include medicament, medication, medicine.

ethical drug (noun)	medicinal drug (noun)
a drug that is available only with written instructions from a doctor or dentist to a pharmacist	(medicine) something that treats or prevents or alleviates the symptoms of disease