Yes I have heard of it. Simply stated, it is similar to flashbacks but of a longer duration and frequency. Hopefully anything else medically has been ruled out before that is diagnosed. Abstinence and time will be key in controlling symptoms and hopefully your son will seek professional guidance for further management. In my experience sometimes other medications are prescribed to ease symptoms.. It is so hard to see our children suffer but it sounds like he was verbalizing some awareness of the seriousness of his situation. As my ad got older it became a little easier to step back and allow her to find her way. I had exhausted myself trying to get her help as a younger teen. No matter what I said, suggested, rephrased, lectured, or set up it was all sabotaged. She did find her way into recovery, and is doing the necessary work herself. It is far from perfect but so much better. There is hope. It is a process. Take good care of yourself.

I've not heard of it but am sending you thoughts and prayers.