Delirium, illegally known as the acute confusional state, is a decline of organic origin that develops over a short period of time, usually from a few hours to a few hours.  Delirium is a syndrome encompassing disorders of attention, consciousness and cognition. It may also involve other neurological deficits, such as psychomotor disorders (for example hyperactive, hypoactive or mixed), alteration of the sleep-wake cycle, emotional disturbances and perception disorders (for example hallucinations).

Delirium is caused by an acute organic process, which is the brain that can cause a physically identifiable structural, functional or chemical problem. It can result from an underlying pathological process (for example, infection, hypoxia), a side effect of medication, withdrawal from medication, overconsumption of alcohol, use of delusional drugs, hallucinogens, or any other factor affecting their overall health. malnutrition, pain, etc.). On the other hand, fluctuations in mental state / function due to changes in major psychiatric processes or diseases (eg schizophrenia, bipolar disorder) do not respond,