substance abuser vs doer

substance abuser and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
substance abuser	Yes	No	No	No
doer	Yes	No	No	No

As nouns, doer is a hypernym of substance abuser; that is, doer is a word with a broader meaning than substance abuser:

Other hypernyms of substance abuser include actor, worker.

substance abuser (noun)	doer (noun)
a person who takes drugs	a person who acts and gets things done