What are opioid mixed agonists?

Pentazocine (agonist k Rs, weak antagonist at mew, analegesia and sedation, less euphoria than morphine, causes dysphoria and psychotomimetic effects, doesn't antagonize resp distress of morphine) Nalbuphine (potent mew antagonist and k agonist, analgesic less dysphoric than pentazocine) Buprenorphine