A friend curtailed drug problem in Arabian city (3,5)
I believe the answer is:
abu dhabi
'arabian city' is the definition.
'Abu Dhabi' can be an answer for 'city' (Abu Dhabi is an example). I am unsure of the 'arabian' bit.
'a friend curtailed drug problem' is the wordplay.
'friend' becomes 'bud' (short for buddy).
'curtailed' means to remove the last letter.
'drug problem' becomes 'dhabi' (I am not sure about this - if you are sure you should believe this answer much more).
'bud' with its final letter taken away is 'bu'.
'a'+'bu'+'dhabi'='ABU DHABI'
'in' is the link.
Can you help me to learn more?
(Other definitions for abu dhabi that I've seen before include "One of the United Arab Emirates" , "in Middle East" , "Persian Gulf emirate" , "M East country" , "Asian capital" .)