I agree to try to convince him to go to a hospital, even if he won't go, he may wake up to how serious this is, and call for emergency support, even 911 if you have to.

I don't want to tell you off. I understand your concerns and frustrations and I know many people feel different about this but, relax about the pot. I don't smoke it myself. I did when I was your son's age but, I know some people with or without mental illness do benefit. It can help him sleep and with the aggitation, and doesn't make a lot of people any more "high" than say klonopin and it is less addictive too...it really isn't much different than any other "natural" remedy in that dosaging may vary and as for effects. Depending on what kind he is smoking and how much, for many people it is not too different from sedating drugs and a lot less side effects. Sure, it is somewhat illegal but, at least where I am, that isn't enforced unless you're trafficking. Either way though, now isn't the time to worry about pot smoking, given it is just pot and not drinking or other drugs getting in the way. Wait until he is stable, with or without medications/psychiatric treatment, to argue about marijuana or make other judgements.

Good luck!