Meat can be a drug! (5)
I believe the answer is:
joint
I believe this clue is a double definition.
'meat' is the first definition.
(joint is a kind of meat)
'a drug' is the second definition.
(joint is a kind of drug)
'can be' is the link.
(Other definitions for joint that I've seen before include "Piece of meat - illegal smoke" , "Cut of meat; mutual" , "eg Knee" , "Flexible link" , "Piece of meat for roasting" .)