Speaking out, you spill the beans on drugs (5)
I believe the answer is:
using
'on drugs' is the definition.
(I've seen this before)
'speaking out you spill the beans' is the wordplay.
I cannot quite see how this works, but
'you' could be 'u' (commonly used in online communication) and 'u' is present in the answer.
'spill the beans' could be 'sing' (both can mean to reveal secrets) and 'sing' is found within the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for using that I've seen before include "Employing" , "Exploiting for one's own advantage" , "having recourse to" , "practice" , "Utilising" .)