An example of a pure opioid antagonist.. Naloxone hcl - Narcan An example of a pure opioid antagonist: a- Naloxone hcl (Narcan)*** b- Pentazocine (Sosegon)i c- Nalbuphine(Nubain)i d- Morphine. Share This: Facebook Twitter Google+ Stumble Digg Email ThisBlogThis!Share to XShare to Facebook