Also, I always promised my son that going to the hospital would be his choice.
And, even though they put him on involuntary holds all 5 times, he would agree to go - just, when he got there, he would want to leave. Or even if he said he wanted to stay, they would say he was too ill to be mentally capable (legally) of consenting, so they would do the hold so he couldn’t change his mind the next day & want to leave.
However, in that promise, I told him if I even had the hint that he was going to hurt himself on purpose or by accident, I wouldn’t have a choice. I’d also rather have him hate me and be alive than love me and be dead.
If you call one of these places, and they come get him and force him into the hospital, you’ve done the right thing. Not eating - I’d write that off to the psychosis. Talking about getting the gun, I could reason in my own head that the idea would pass. I could make myself think the overdose was just one of those things my son does when he pushes the edge.
Giving the dog away, to me anyway, means he is dead serious, has a plan & means to act.
Plus, on new meds, don’t they usually tell you to watch for changes in mood, especially suicidal thoughts & actions?
It sounds like you have every reason to believe his current meds are making things worse & that’s also a perfect reason to get an involuntary hold.