Succeeded without drugs to become absolutely clean (8)
I believe the answer is:
spotless
'absolutely clean' is the definition.
(I've seen this before)
'succeeded without drugs to become' is the wordplay.
'succeeded' becomes 's' (genealogical abbreviation).
'without' is an insertion indicator.
'drugs' indicates an anagram (I've seen 'drugged' mean this).
'become' becomes 'pless' (I am not sure about this - if you are sure you should believe this answer much more).
'to' is an anagram of 'ot'.
'ot' put into 'pless' is 'potless'.
's'+'potless'='SPOTLESS'
Can you help me to learn more?
(Other definitions for spotless that I've seen before include "showing no sign of acne?" , "Spic-and-span" , "honest!" , "Absolutely pure, clean" , "Without blemish" .)