drug-addicted vs dependant

drug-addicted is not a noun while dependant is a noun.

Word	Noun	Adjective	Verb	Adverb
drug-addicted	No	Yes	No	No
dependant	Yes	Yes	No	No

As adjectives, drug-addicted and dependant are synonyms defined as:

Other synonyms of drug-addicted include dependent, hooked, strung-out.

drug-addicted (noun)	dependant (noun)
	a person who relies on another person for support (especially financial support)

drug-addicted (adjective)	dependant (adjective)
addicted to a drug	addicted to a drug
	contingent on something else