Without knowing the specifics, if you have substance abuse problems that are concerning enough for you to "resign" an anesthesia position in your last year of training, a career in pain management in which you would be prescribing narcs frequently, doing injections, etc. sounds like a bad idea simply due to access/opportunity. From an intellectual standpoint, it makes sense to minimize dealing with or prescribing medications with high abuse potential on a regular basis. I am not a PD, but I would question someone coming into my program wanting to specifically do pain mgmt who has had a very recent problem. Do you have an interest in PMR outside of pain management? You will need to be forthcoming about this issue with future PDs/employers/hospitals since every license, credentialing, insurance, etc. application specifically asks about substance abuse problems. Getting a license in a new state may be contigent upon enrolling in the new state's monitoring program, depending on the licensing board. If the problems are in the remote past, it shouldn't be an issue and won't hold things up so long as you provide all the requested information and followed rules as set by the monitoring group and licensing board. But until it is truly "in the past" and you have proven to be a safe and sober provider, you may find yourself under more scrutiny and have a tougher time finding a (pain) position.