Agonist/Antagonist Opioid Analgesics. When a client has Beforehand obtained or is currently undergoing a training course of therapy with a pure opioid agonist analgesic like Dilaudid, agonist/antagonist analgesics like pentazocine, nalbuphine, butorphanol, and buprenorphine, should be used with warning.When this medication is used for the long ti