Described below is one of the many approaches I've tried or considered trying for healing my chronic myofascial pain:
BOTTOM LINE: Hardly worked.
I took painkillers (e.g., oxycodone, hydrocodone) when I first ruptured my disc (before surgery) and they barely had an effect on my excruciating pain (although I did welcome the one hour of slight relief I'd get in the four hours they were supposed to work). After my surgery I took them, too. But when weeks turned to months and they were not reducing my still daily, debilitating pain, I stopped taking them. In fact, lying down to relieve my neck pain actually worked better than the drugs (and didn't have side effects, except for limiting my daily activities).
I know for some people these work and when pain is acute and intense, they help the body begin to heal. Sadly there is a war going on against opioids making life miserable for pain patients who truly need them. And also sadly, some people who need them at first to control pain end up getting addicted to them. I believe that the more we can address underlying sources of pain (e.g., emotions/trauma) to reduce our pain and dependence on medications, the better off many of us will be.