immunosuppressant vs immunosuppressor

immunosuppressant and immunosuppressor both are nouns.

Word	Noun	Adjective	Verb	Adverb
immunosuppressant	Yes	No	No	No
immunosuppressor	Yes	No	No	No

As nouns, immunosuppressant and immunosuppressor are synonyms defined as:

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

Other synonyms of immunosuppressant include immune suppressant drug, immunosuppressive, immunosuppressive drug.

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