Drinks with added recreational drug — moral shortcoming (5)
I believe the answer is:
lapse
'moral shortcoming' is the definition.
(I've seen this before)
'drinks with added recreational drug' is the wordplay.
'drinks' becomes 'laps' (lapping is a kind of drinking).
'with added' is a charade indicator (letters next to each other).
'recreational drug' becomes 'e' (E can refer to ecstasy).
'laps'+'e'='LAPSE'
(Other definitions for lapse that I've seen before include "Temporary failure of judgment or concentration" , "Decline - pass away" , "Slip-up" , "Careless mistake" , "Slight error due to forgetfulness" .)