Squalid son getting idle consuming drug (6)
I believe the answer is:
sleazy
'squalid' is the definition.
('sleazy' can be a synonym of 'squalid')
'son getting idle consuming drug' is the wordplay.
'son getting' becomes 's' (I've seen this in other clues).
'idle' becomes 'lazy' ('lazy' can be similar in meaning to 'idle'**).
'consuming' indicates putting letters inside.
'drug' becomes 'e' (e is another name for ecstasy).
'lazy' placed around 'e' is 'leazy'.
's'+'leazy'='SLEAZY'
(Other definitions for sleazy that I've seen before include "Sordid, corrupt" , "Tacky" , "Morally degraded" , "Dirty or dishonest" , "Squalid, tawdry" .)