immunosuppressant vs immune suppressant drug

immunosuppressant and immune suppressant drug both are nouns.

Word	Noun	Adjective	Verb	Adverb
immunosuppressant	Yes	No	No	No
immune suppressant drug	Yes	No	No	No

As nouns, immunosuppressant and immune suppressant drug are synonyms defined as:

immunosuppressant and immune suppressant drug: a drug that lowers the body's normal immune response

Other synonyms of immunosuppressant include immunosuppressive, immunosuppressive drug, immunosuppressor.

immunosuppressant (noun)	immune suppressant drug (noun)
a drug that lowers the body's normal immune response	a drug that lowers the body's normal immune response