The drugs in use for Schizophenia are extremely powerful drugs and as such are very hazardous in use. Indeed, use of some of them have to on a special register. The main problem is that without the drugs the patient cannot lead a normal life. This has been demonstrated by the actions of some schizophrenics who stop taking that medication.
Most drug induced abnormalities are subclinical and there are no therapies available to correct them. This means that there are no signs for the doctor to pick up on.
These medications make the patient feel poorly, so naturally they want to stop taking them. They do indeed upset the neuroendocrine system and create other associated problems, but what is the alternative solution?
This is a real catch 22 situation.