Drunken employee originally breathalysed, perhaps couldn't stand (8)
I believe the answer is:
detested
'couldn't stand' is the definition.
(I've seen this before)
'drunken employee originally breathalysed perhaps' is the wordplay.
'originally' indicates taking the first letters.
'breathalysed perhaps' becomes 'tested' (breathalysing is a kind of testing).
The first letters of 'drunken employee' is 'de'.
'de'+'tested'='DETESTED'
(Other definitions for detested that I've seen before include "Loathed over test deed" , "Couldn't stand trial" , "Disliked intensely" , "Unpopular" , "not at all popular" .)