Delirium is recognized by the presence of a number of specific symptoms, but these may change quickly.  For example, someone may move from lethargy to agitation and then back again. The symptoms also vary quite a bit from one person to the next. Delirium may also come and go within a 24-hour period and people with delirium often have lucid (clear) intervals during the course of a day. 

Typical symptoms of delirium include:

• Sudden onset over hours to days
• Slurred speech and language difficulties, talking that doesn’t make sense
• Changes in feeling (sensation) and perception
• Easily distracted, decreased attention, concentration, and environmental awareness; usually more alert in the morning than at night; in and out of consciousness
• Changes in movement (for example, may be slow moving or very restless)
• Changes in sleep patterns, such as reversed sleep-wake cycles
• Confusion and disorientation, not aware of correct time or place
• Memory loss, including decreased short-term memory and recall
• Disorganized thinking
• Emotional or personality changes, with frequent changes in moods, including anger, agitation, anxiety, apathy, depression, fear, euphoria, irritability, suspicion
• Incontinence
• Hallucinations (visual, but not auditory)
• Signs of medical illness (such as fever, chills, pain, etc.) or medication side effects

Last Updated July 2020