Drinker serves up some bizarre potations (5)
I believe the answer is:
toper
'drinker' is the definition.
('toper' can be a synonym of 'drinker')
'serves up some bizarre potations' is the wordplay.
'serves up' says the letters should be written in reverse.
'some' indicates a hidden word (some of the parts of the word are used).
'repot' can be found hidden inside 'bizarre potations'.
'repot' backwards is 'TOPER'.
(Other definitions for toper that I've seen before include "Excessive drinker" , "Drunkard" , "Tippler" , "Someone with a drink problem" , "Wino" .)