I have a pug as my psychiatric service dog. I have many mental disorders..
(Psychosis NOS, Anxiety NOS, Severe Depression, Severe OCD (which is in Anxiety NOS), ADHD, and some undiagnosed eating disorders.)
...and my dog really helps me!
I'm getting a cat soon as well (:
my pug is on my profile, I believe... I think its the only pic i have on this site.
i will make him my avatar, soon (:
and as for getting a dog for services... you must be courageous enough to demand to your psychiatrist that it is absolutely necessary (which it was for me.)
especially because I basically live in strict isolation, (an apartment, and I don't talk to many people) I would go mad without my dog.
I think it's important to state it to the psychiatrist like this:
"You know, I've been feeling very ____ lately and i really don't know what to do. I recently found out about psychiatric service dogs, and I really am interested! I know it would help me. I would have a being to care for, other than myself. It would be very helpful. Can you see what you can do about this?"
Something like that. Because just tell them how it would help you in social ways.... basically, ways that medication canNOT help.

Like, how you might meet new friends while walking the dog at the park.
My mother, who helps me care for my puggy, has met SO many friends while walking the dog. So have I. And it really helps me open up.

Many autistic children/adults (of all spectrums) would greatly benefit from canine companionship because it would help them to learn proper social skills, as well as meeting new people.

I think having a dog has helped me accept myself more, also... because it has given me the gift of unconditional love. (the dog gives me unconditional love, which definitely makes me feel better about myself.)
I also love the dog unconditionally, which makes me more kind of a person.

It's really like how starting a family can soften a person's heart.


So there you go, here's some things you could tell to your psychiatrist, if they apply to you.
You could say you would be helped tremendously, with all the things that dogs help with that I mentioned above.

G'luck ! x