Fatigue (low energy) may accompany cognitive decline in some people living with dementia, including Alzheimer’s disease. Often called dementia fatigue, this symptom occurs in a lot of people who have memory problems or cognitive impairments (trouble thinking), both with and without an Alzheimer’s diagnosis.

If you’re the caregiver of someone who has Alzheimer’s, here’s what you need to know if they develop dementia fatigue.

Is It Normal for Someone With Dementia To Sleep a Lot?

Yes, in some cases, people with dementia experience extreme fatigue. “Dementia fatigue” is exactly what it sounds like — tiredness or exhaustion in people who have various types of dementia or Alzheimer’s. Dementia can disrupt sleep patterns and energy levels, leading to frequent daytime naps or trouble waking up in the morning.

Many people with dementia fatigue want to sleep more. One myALZteam caregiver described the challenges of getting their loved one out of bed each morning: “He argues with me every day. After sleeping 15 to 17 hours, he says he’s tired.”

Others find that they can’t do as much with their loved one as they used to. “It felt good to be out, as we are pretty limited in what we do now due to hubby’s fatigue,” another member shared.

People with Alzheimer’s may notice their own fatigue. “My health is going downhill, and when I’m sleeping, it is usually 14 hours a day. I wake up tired and stay tired until I nap,” a member living with Alzheimer’s said.

“My health is going downhill, and when I’m sleeping, it is usually 14 hours a day. I wake up tired and stay tired until I nap.”
— A myALZteam member

Dementia Fatigue Differs From Sundowning

Sundowning, another common symptom of dementia, may be related to fatigue. “Sundowning” refers to the increased confusion, forgetfulness, anxiety, irritation, or agitation that people with Alzheimer’s and other dementia types experience in late afternoon, during the evening, or at night.

People may become more anxious, pace, have hallucinations, or feel agitated, which can make it hard to sleep at night or may cause sleep disturbances. Reduced nighttime sleep quality could cause more daytime sleepiness.

Brain Changes May Cause Excessive Sleeping

Not all fatigue associated with Alzheimer’s is caused by a lack of sleep due to sundowning. Researchers don’t know exactly what causes Alzheimer’s fatigue. Some cases may be tied to changes in the parts of the brain related to the condition. A 2022 study found that Alzheimer’s may damage specific brain cells involved in staying awake. As a result, people with the condition may feel excessively sleepy during the day, even after a full night’s rest.

Alzheimer’s-related brain changes can disrupt the body’s biological clock — also known as the circadian rhythm — which helps regulate sleep and wake cycles. When this clock is affected, a person may wake up at unusual times or feel sleepy throughout the day, even after resting well at night.

Dementia Fatigue May Be Related to Age

As people age, they may experience more daytime drowsiness and fatigue. These symptoms are linked to brain changes that can also be seen in Alzheimer’s disease. For example, the temporal cortex thins, and the hippocampus often shrinks. These changes resemble patterns found in Alzheimer’s disease, too.

It’s not clear why these symptoms occur. Changes in sleep patterns and fatigue may cause changes in the brain, or changes in the brain may lead to fatigue and increased sleepiness. More research is needed to determine how these processes are connected.

Medications May Cause Fatigue

A number of medications can cause excessive sleepiness. Some drugs may be prescribed as interventions for Alzheimer’s or other conditions. Anti-anxiety medications, antidepressants, antihistamines, and blood pressure drugs can cause low energy, sleepiness, and fatigue as side effects.

If your loved one suddenly developed fatigue instead of getting more tired over time, it may be time to look over their list of medications with a doctor or pharmacist to make sure the medicine is not the problem.

Dementia Fatigue Can Lead to Poor Nutrition

Some people feel too tired to eat and seem to lose interest in food. “My loved one won’t eat breakfast and just wants to sleep,” one caregiver noted.

When this happens, it can be hard to help a person with Alzheimer’s get the nutrition they need to stay well. Talk with your loved one’s healthcare team to get the solutions you need.

Fatigue Often Worsens as Alzheimer’s Progresses

Fatigue and time spent sleeping or in bed are likely to increase as dementia progresses from early stages to later stages. Near the end of life, a person living with Alzheimer’s or another form of dementia may not be able to get out of bed or a chair without help. The combination of fatigue and disorientation may make movement very difficult.

Spending the Day Lying Down Can Cause Bedsores

It’s important to make sure that your loved one doesn’t develop bedsores or other physical ailments that can come from lying in bed most of the day. If you work with medical staff who care for your loved one regularly, they’ll usually take steps to prevent these problems. Otherwise, talk with your loved one’s doctor about how you can ensure they stay healthy even as they sleep more.

It’s important to make sure that your loved one doesn’t develop bedsores or other physical ailments that can come from lying in bed most of the day.

A Doctor Can Address Increased Fatigue

Whether your loved one is experiencing new fatigue or has been tired for a while, it’s important to address this as part of their dementia care. Their doctor can help you look over their medications, possibly changing out any that could be causing the fatigue.

Their healthcare provider can also help you come up with plans for managing eating issues, sundowning, and more. They can also help you determine whether the fatigue needs to be improved or if you can simply let your loved one sleep when they want.

Join the Conversation

On myALZTeam, people share their experiences with Alzheimer’s, get advice, and find support from others who understand.

Have you found ways to manage dementia fatigue, or are you looking for solutions? Let others know in the comments below.