Schizophrenia is caused by multiple factors such as genetics, developmental problems, as well drug use. A person’s chance of developing this disorder increases if she or he has a direct relative who is/was schizophrenic. However, environmental situations such as viral infections and lack of nutrients during an infant’s developmental stage can increase a child’s risk of developing schizophrenia. According to WebMD, psychoactive drugs can also cause schizophrenia by invoking hallucinations.