If work comp claim, you pretty much have to do what the dr says..
But usually the PT sends a progress report to the dr, or you have a appt with dr before the dr releases you back to work. And the dr can include job limitations..in the release note.
The limit can be hours, days, break times, lifting or computer time limits.. but you & employer need to follow those. If employer can't fit a job to those limits, they can make you stay home..

So basically communicating with your doc is very important and make sure they understand any pain or symptoms you are still having..
I had to have my job restrictions rewritten a few times for clarification, as employer had me doing work that was making my pain increase.

Unfortunately if the pain med covers up the pain, it isn't "fixing" the problems, just covering up the pain.. when the time comes, be sure to ask if you will be injuring yourself more if you go to work while still on the med..