Psychosis
Definition
Psychosis is a symptom or feature of mental illness typically characterized by radical changes in personality, impaired functioning, and a distorted or nonexistent sense of objective reality.
Description
Patients suffering from psychosis have impaired reality testing; that is, they are unable to distinguish personal subjective experience from the reality of the external world.
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With regard to substance abuse, several different research groups reported in 2004 that cannabis (marijuana) use is a risk factor for the onset of psychosis.
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Substance-induced psychotic disorder
Psychosis is also a known side effect of the use, abuse, and withdrawal from certain drugs. So-called recreational drugs, such as hallucinogenics, PCP, amphetamines, cocaine, marijuana, and alcohol, may cause a psychotic reaction during use or withdrawal.