Immobilization and positioning goes a long way for controlling pain. I see all sort of injuries that can have pain managed with basic measures at certain times, which are very much a part of the continuum of pain control. Pain control does not equal meds all the time. Most patients with patellar dislocation are happy with out waiting for an IV and meds to kick in when I can reduce it, have it immobilized, get them crutch training, and have them out the door with ortho follow-up in less than 15 minutes from time of arrival. Now, if it seems they may not tolerate the reduction or are in serious pain at rest, then yes an IV, morphine or dilaudid, and x-rays before we touch it.
Don't bother reasoning with him. Not worth your time. I learned the hard way.