Some of you might be interested to read this Australian news article. I should make clear that I have no special knowledge of this, just that it popped up on my Oz news site.
That being said, half the battle is getting that person diagnosed, them accepting their diagnosis, and taking treatments as prescribed. That is the tough part of this equation. Case in point: my mother had schizophrenia that was so bad she needed treatment for it, but she refused to accept that she had a problem. Because she didn't think there was anything wrong with her, she never took her meds, refused to see a doctor, etc. Meanwhile, she just got worse until finally she had to be committed to a mental hospital when I was nine. Two years later, still not taking treatments, she got so bad that it made her violent and my father and I had to leave.
Prescriptions only work if the patient takes them.