Men make drugs available for rigorous trial (6)
I believe the answer is:
ordeal
'rigorous trial' is the definition.
'men make drugs available' is the wordplay.
'men' becomes 'or' (military abbreviation for Other Ranks).
'make drugs available' becomes 'deal' (as in drug-dealing).
'or'+'deal'='ORDEAL'
'for' acts as a link.
(Other definitions for ordeal that I've seen before include "Trial; nightmare" , "Tribulation" , "severe test shows" , "Long painful experience" , "Severe or trying experience" .)