Guy takes a drink in a stupor (9)
I believe the answer is:
catatonic
'in a stupor' is the definition.
(catatonic can mean in a stupor)
'guy takes a drink' is the wordplay.
'guy' becomes 'cat' (American slang for man, esp in Jazz).
'takes' is a charade indicator (letters next to each other).
'drink' becomes 'tonic' (tonic is a kind of drink).
'cat'+'a'+'tonic'='CATATONIC'
(Other definitions for catatonic that I've seen before include "Rigid and in a stupor through illness" , "Not very lively" , "Having muscular rigidity and stupor" , "Stupefied and immobile" , "In a stupefied state" .)