Depleted (4,2)
'depleted' is the definition.
('use up' can be a synonym of 'deplete')
This is all the clue.
(Other definitions for used up that I've seen before include "Spent" , "Consumed, finished" , "Consumed completely" , "Exhausted the supply" .)
(Other definitions for emptied that I've seen before include "Evacuated" , "Made vacant" , "having nothing more to offer" , "Made void" , "Discharged" .)