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Delirium and dementia

​​​​​​​​​What's the difference between delirium and dementia?​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

Delirium comes on suddenly over a few hours, or a few days. For example, you’re more confused, agitated or even sleepier than usual. It may be temporary, but can last from a few days to several weeks. In some cases, it may take weeks or months to recover.

Dementia is a slow, steady decline in function over several months or years. Alzheimer’s disease is 1 type of dementia.

Delirium in someone with dementia can be hard to recognize. You may notice a sudden change in their behavior. You may also notice that they aren’t able to do things as well as they usually can or have trouble paying attention. An important first step is to tell your doctor, nurse, or other healthcare provider about the changes you see in yourself, a friend, or family member. Small changes caught early can make a difference.

If you have questions about delirium or dementia call Health Link at 811. You can talk to a registered nurse​ and ask about the Dementia Advice Line.

Current as of: May 26, 2022

Author: Provincial Seniors Health and Continuing Care, Alberta Health Services