Monitor about to resort to drink (10)
I believe the answer is:
chartreuse
'drink' is the definition.
(Chartreuse is an example)
'monitor about to resort to' is the wordplay.
'monitor' becomes 'chart' (to chart something is to track or monitor it).
'about to' becomes 're' (I've seen this in other clues).
'resort to' becomes 'use'.
'chart'+'re'+'use'='CHARTREUSE'
(Other definitions for chartreuse that I've seen before include "The spirit" , "green liquid" , "Green-yellow liqueur" , "Carthusian liqueur" , "Pale green-yellow colour" .)