Hallucinations that involve seeing, feeling, smelling, or tasting often reflect a medical problem. There are many types of delusions. A short-term psychosis is often related to exposure to certain drugs or substances. Certain medical conditions can also result in psychosis. Many other medical problems can cause psychosis, such as problems with the brain or nervous system.
People can even become psychotic from a severe lack of sleep.
People with bipolar disorder often become psychotic in the manic or depressed phases of their illness. Many psychotic disorders are long-term. The most common is schizophrenia, which usually involves problems with hallucinations or delusions throughout the person's adult life. It is important that people who have any kind of psychosis be examined by their doctor. They may also need to see a mental health provider.