Consumed by marijuana, the man's curse (8)
I believe the answer is:
anathema
'curse' is the definition.
(anathema can mean a curse)
'consumed by marijuana the man's' is the wordplay.
'consumed by' indicates the answer is hidden within the clue (inserted letters get consumed).
'ANATHEMA' is hidden in the letters of 'marijuana the man'.
(Other definitions for anathema that I've seen before include "Formal curse leading to excommunication" , "Something one vehemently dislikes" , "thing we detest" , "odious" , "Curse - church ban" .)