anxietygirl,
I'm so very sorry you are going through such a rough time with your son...

Can you put in another call to his pdoc tomorrow?

It's truly hard for me to understand why they could not keep him--unless he lied and led them to believe he was "better"...not suicidal at the moment.

Jmo, perhaps taking him to the ER for his withdrawal symptoms would be a good idea. Going cold turkey off those drugs can be dangerous and he may need to be monitored.
Are you sure, though, that he has not ingested any type of poison??

Cap