Long article about heroin and ecstasy (4)
I believe the answer is:
ache
'long' is the definition.
(to long for something is to ache for it)
'article about heroin and ecstasy' is the wordplay.
'article' becomes 'a' (the indefinite article in English).
'about' becomes 'c' (abbreviation for circa).
'heroin' becomes 'H' (H is a slang term for heroin).
'and' says to put letters next to each other.
'ecstasy' becomes 'E' (informal term for the drug).
'a'+'c'+'h'+'e'='ACHE'
(Other definitions for ache that I've seen before include "Twinge" , "Dull steady pain" , "Pine" , "Feel pain" , "Dull throbbing pain" .)