I'm so sorry. I know that panicky feeling all too well. BTDT many times. You feel like you want to run, scream, beat something or SOMEONE!
But you know what? It always passes. You'll get through it and come back down to earth. I hope this is a lesson to your ds and if he gets out of this situation, I hope it scares him enough to learn from. Many addicts relapse. It happens, but it's so hard to deal with it when it does happen. It's like trying to stop a freight train.
Deep breaths and again I'm sorry.