Compound

Receptor types

m k s
Morphine Ag Ag --
Naloxone Ant Ant mixed
Pentazocine Ant Ag Ag
Butorphanol -- Ag Ag
Nalbuphine Ant pAg mixed
Nalorphine Ant pAg mixed
Buprenorphine pAg ? --

Ag = agonist; Ant = antagonist; pAg = partial agonist: -- = nosignificant action.