Alzheimer's disease tends to develop slowly over time. If confusion and other changes in mental abilities come on suddenly, within hours or days, the problem may be delirium, a condition that needs immediate treatment.



Seek care immediately if:

Symptoms such as a shortened attention span, memory problems, or seeing or hearing things that aren't really there (hallucinations) develop suddenly over hours to days.

A person who has Alzheimer's disease has a sudden, significant change in normal behavior or if symptoms suddenly become worse.



Call your doctor to schedule an appointment if:

Symptoms such as a shortened attention span, memory problems, or false beliefs (delusions) develop gradually over a few weeks or months.

Memory loss and other symptoms begin to interfere with the person's work or social life or could result in injury or harm to the person.

You need help caring for a person with Alzheimer's disease.