drug user vs worker

drug user and worker both are nouns.

Word	Noun	Adjective	Verb	Adverb
drug user	Yes	No	No	No
worker	Yes	No	No	No

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

Other hypernyms of drug user include actor, doer.

drug user (noun)	worker (noun)
a person who takes drugs	sterile member of a colony of social insects that forages for food and cares for the larvae
	a person who works at a specific occupation
	a member of the working class (not necessarily employed)
	a person who acts and gets things done