What Is Delirium?

Delirium is a sudden decline in a person’s usual mental function. It occurs when signals in the brain aren’t sending and receiving properly, causing confusion i

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Delirium is a sudden decline in a person’s usual mental function. It occurs when signals in the brain aren’t sending and receiving properly, causing confusion in thinking and altered behavior or levels of consciousness.

Delirium isn’t a disease; it’s a clinical syndrome or condition that is usually temporary and treatable. It’s often mistaken for dementia because both conditions have similar symptoms, such as confusion, agitation, and delusions. If a health care professional doesn’t know the patient, it can be difficult to tell the difference.