Deteriorates and becomes a drug-taker (4,2,3)
I believe the answer is:
goes to pot
'deteriorates' is the definition.
(I've seen this before)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for goes to pot that I've seen before include "Prepares to follow snooker player" , "Become ruined" , "loses form" , "cracks up" , "Approaches the snooker table" .)