Drunk concerned with vessel that's tipped over (5)
I believe the answer is:
toper
'drunk' is the definition.
(toper can mean a drunken person)
'concerned with vessel that's tipped over' is the wordplay.
'concerned with' becomes 're' (re can mean regarding, concerning).
'vessel' becomes 'pot' (type of container).
'that's tipped over' says the letters should be written in reverse.
're'+'pot'='repot'
'repot' backwards is 'TOPER'.
(Other definitions for toper that I've seen before include "Alcoholic" , "Someone with a drink problem" , "Excessive drinker" , "Regular drinker" , "Drinker, imbiber" .)