However, it is not the same as a split or multiple personality. Multiple personality disorder is a separate, extremely rare condition. It's also important to note that, although some people with schizophrenia develop violent tendencies, most do not. In fact, many withdraw into themselves rather than interact with others. Not everyone who acts paranoid or distrustful is schizophrenic.
Some people have what's called paranoid personality disorder.
He also notes that some people with depressive disorders may have paranoid features. Other causes of paranoia include substance abuse, particularly with stimulants such as amphetamines and methamphetamines but also with heavy use of alcohol and marijuana. Schizophrenia may exist alone or in combination with other psychiatric or medical conditions. A person with schizophrenia who is dependent on alcohol or other drugs, for example, requires more complex treatment than does someone with schizophrenia alone. New generation drugs Neuroleptic drugs, also called antipsychotic drugs, have been the cornerstone of schizophrenia treatment for many years.