hallucinogen vs hallucinogenic drug

hallucinogen and hallucinogenic drug both are nouns.

Word	Noun	Adjective	Verb	Adverb
hallucinogen	Yes	No	No	No
hallucinogenic drug	Yes	No	No	No

As nouns, hallucinogen and hallucinogenic drug are synonyms defined as:

hallucinogen and hallucinogenic drug: a psychoactive drug that induces hallucinations or altered sensory experiences

Other synonyms of hallucinogen include psychedelic drug, psychodelic drug.

hallucinogen (noun)	hallucinogenic drug (noun)
a psychoactive drug that induces hallucinations or altered sensory experiences	a psychoactive drug that induces hallucinations or altered sensory experiences