Agitation, restlessness, irritability, confusion and disorientation are common symptoms of Sundown syndrome, notes WebMD. People with Sundown syndrome may also be demanding and suspicious, yell, hear or see things, and have mood swings.
While about 20 percent of people with Alzheimer's disease suffer with Sundown syndrome, it can affect older people who do not suffer from dementia, states WebMD. People with Sundown syndrome tend to show changes in their behavior in the late afternoon and early evening, as light fades. While doctors do not know the cause of Sundown syndrome, as of 2015, some scientists believe that it is caused by brain changes that interfere with the body's internal clock.
Less light and more shadows in the house, trouble separating dreams from reality, and picking up on the frustration of others can trigger episodes of Sundown syndrome, notes WebMD. People caring for those with Sundown syndrome can help by noting triggers, scheduling activities for earlier in the day, closing curtains and turning lights on as it gets darker outside, and getting rid of clutter. Staying calm, not arguing, being reassuring and putting away dangerous objects are ways in which people can help those in the middle of a Sundown syndrome episode. There is no known cure for Sundown syndrome, as of 2015.