Hi! I believe I can be of help with this issue.
First, let me say I can imagine how frustrating this situation must be for you. On the one hand your son is an adult and needs to be treated as one where it is his responsibility to care for himself. But on the other hand you as his family feels it is their duty to help him through this scary and potentially dangerous period in his life.
And this is actually the key to my answer to you that you need to consider and think about. YOu are correct that these symptoms of delusions and hallucinations are dangerous if not treated. They are dangerous both because of what he might do and because of the damage that untreated schizophrenia does to the person's brain. But it is important for you to be on his side. Why?
One of the problems here is that with many schizophrenia sufferers, manipulating the situation to avoid treatment in general is part of the disorder. It is very pernicious and very difficult to treat. I would like to recommend to you the work of Dr. Xavier Amador. I think that in this area of treatment resistance he has been invaluable to all of us working with schizophrenia. I know some people don't go for his style, but I have found it very valuable and I think you will see its value as well. His whole approach is to find the way to make treatment a win-win situation. Because for your son, treatment is only for others' sakes: family, doctors, etc. Not for himself.
So this approach can help you very much. Here are his two most known books:
I am Not Sick, I Don't Need Help. This is the book that made Dr. Amador famous. It details a bit the story of his brother, who will remind of you of Leo probably in some aspects. Amazon page for it:
The other book is I'm Right You're Wrong, Now what? Break the Impasse and Get What You Need. Amazon page:
So, read Dr. Amador's work and digest the idea. I don't know if the Dr. John Horton you are looking for is the psychiatrist in Seattle, WA. If so, I believe he is still in practice. But whatever the situation with finding him a specific psychiatrist, you need to work with a method for getting him to agree to getting help in the first place. So work on Dr. Amador's principles as soon as you can.
I wish you the very best!
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