Our current state of civilized development and social engineering fairly preclude our ability to effectively deal with most of the mental physiologic problems we generally contend with on an internal level, so external manipulation of the chemistry/physiology of our bodies seems to be the only method that will work for most of us.
First of all, I am not a mental health professional. However, I work in a large urban public library that is visited every day by a lot of mentally ill people - I wind up dealing with many of them. Most are simply "odd" but others are profoundly mentally ill and when they're off their meds they are completely unable to deal with society - I recall a man wrestling with four LEOs who tased and sprayed him and then the man put one of the officers out of commission for 6 months ... they finally put leg shackles on the man, in addition to cuffs (the man still comes to the door and I have to tell him he can't come into the building - he is now cool, calm, and collected and on his meds). I would suggest that maybe many people with mild to moderate mental illness might be helped without using meds but profoundly mentally ill people probably cannot.
My $.02
Wheels