prescription medicine vs ethical drug

prescription medicine and ethical drug both are nouns.

Word	Noun	Adjective	Verb	Adverb
prescription medicine	Yes	No	No	No
ethical drug	Yes	No	No	No

As nouns, prescription medicine and ethical drug are synonyms defined as:

prescription medicine and ethical drug: a drug that is available only with written instructions from a doctor or dentist to a pharmacist

Other synonyms of prescription medicine include prescription, prescription drug.

prescription medicine (noun)	ethical drug (noun)
a drug that is available only with written instructions from a doctor or dentist to a pharmacist	a drug that is available only with written instructions from a doctor or dentist to a pharmacist