Some people have psychotic symptoms due to undetected medical disorders, so medical examinations and laboratory tests should be done to rule out other causes of symptoms. Chidren under the age of five can develop schizophrenia, but it is very rare before adolescence. Nearly 3 million Americans are expected to develop schizophrenia during the course of their lives. There is no known single cause of schizophrenia. It appears that genetic factors produce a vulnerability to schizophrenia, with non-genetic factors contributing in varying degrees in different individuals.
Schizophrenia runs in families.
Most researchers now agree that parents do not cause schizophrenia. No neurochemical cause has yet been established for schizophrenia, but this is an area of research, as is the possibility of schizophrenia being linked to physical abnormalities in the brain. They do have side effects, many of which can be controlled by adjusting the dose. Long-term side effects may be more serious. Rehabilitation, psychotherapy and self-help groups may be helpful.