Sundown Syndrome 101 – Everything You Need to Know

Caring for a loved one with dementia-related symptoms is never easy, although dementia caregivers may notice that symptoms worsen later in the day. While people cannot currently find a description of this phenomenon in the DSM-5, it isn’t imaginary. Because so many report that patients with dementia show worsening symptoms as the sun goes down, there is a widely used, unofficial term to describe it: sundown syndrome.

What is Sundown Syndrome?

Also known as:

  • Sundowning
  • Late-day confusion
  • Sundowners syndrome
  • Sundowner’s syndrome

Sundown syndrome is a range of symptoms that emerges or worsens in older adults, especially those with dementia-related memory loss. The condition is so named because it occurs in the late afternoon, early evening hours, or at night after the sun goes down.

While the term is commonly used, sundown syndrome is not actually a formally recognized condition, according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5).

Symptoms of Sundown Syndrome

Because the DSM-5 does not formally recognize sundowning, there is no standard definition for the condition or its symptoms.

What most people agree upon, however, is that:

  1. Symptoms emerge at a later time of day
  2. Symptoms emerge primarily in people with Alzheimer’s disease (AD), although they may also occur in people with other types of dementia or even geriatric people without dementia

Behavioral symptoms of late-day confusion typically include new or worsening:

  • Anxiety
  • Pacing
  • Agitation
  • Stress
  • Aggression
  • Confusion and disorientation
  • Hallucinations
  • Mood swings or other behavioral changes
  • Wandering

Causes and Risk Factors

Experts are not entirely sure why some people experience sundowning and others do not, although it seems to be more common among older adults who experience some form of dementia-related memory loss

Stress from environmental factors and mental and physical exhaustion may trigger this condition. Researchers believe that the following could contribute to these triggers and therefore sundowning behaviors:

  • AD or another form of dementia
  • Chronic pain syndrome
  • Circadian rhythm disorders, or disorders that interfere with the internal body clock
  • Cognitive decline
  • Low-light environments
  • Medication interactions and side effects
  • Seasonal changes
  • Sleep problems or disorders like sleep apnea
  • Changes in body temperature

Dementia and Sundowning

Anywhere from 2.4% to 66% of people with dementia experience sundown syndrome, according to various reports. The Alzheimer’s Society states that it is more common for people in the middle to late stages of Alzheimer’s disease or another form of dementia to experience this phenomenon. That said, late-day confusion can occur at any stage of dementia, or even in people who do not have dementia at all.

Authorities believe that changes to the brain and stresses that occur from Alzheimer’s may contribute to sundowning behaviors, which is why this condition is so common among people with dementia.

5 Treatment Methods

Family members caring for loved ones experiencing this condition should know that there is no one-size-fits-all treatment for sundown syndrome. That doesn’t mean that there is no hope for improving symptoms, however; it might just take some time before finding the right method that works for their loved ones.

According to one literature review, some research suggests that, among others, the following treatments may help people with dementia and/or sundowners syndrome:

  1. Acetylcholinesterase (AChE) inhibitors
  2. Antipsychotics
  3. Environmental interventions/behavioral modifications
  4. Bright light therapy
  5. Melatonin

Some people claim that other treatments, like acupuncture or aromatherapy, help people with these conditions, too. However, there is limited clinical research to back these claims. While finding a treatment is important, it’s always necessary to use methods that have been extensively backed by research and are approved by a doctor.

1. AChE Inhibitors

Also known as:

  • AChE inhibitors
  • AChEIs
  • Cholinesterase inhibitors

Acetylcholinesterase inhibitors are medications that help block the actions of the enzyme acetylcholinesterase. This enzyme’s job is to break down acetylcholine, a neurotransmitter, which is a chemical messenger in the brain. In the United States, doctors usually prescribe these medications to help treat symptoms of conditions like AD or Parkinson’s disease.

Current research is mixed on whether these drugs help patients with sundowners syndrome. In other words, some studies suggest that these drugs do not help or may even worsen certain symptoms, such as insomnia. Yet other studies alternatively suggest that these medications can help certain people experiencing late-day confusion.

Because the research is mixed, people should talk to their doctors about whether using these medications is the right choice for themselves or loved ones who experience sundowning.

2. Antipsychotics

Also known as:

  • Neuroleptics

Antipsychotics are medications that people most often use to treat conditions like schizophrenia, although doctors may sometimes prescribe them for other conditions, such as dementia, delirium, and Parkinson’s disease.

Some doctors may prescribe these medications to help manage certain symptoms, such as hallucinations; these symptoms may present in people with sundowning. Some research suggests that atypical antipsychotics can be extremely effective in treating unwanted symptoms in older adults, although they also come with their own risks. As such, people should discuss with their doctors whether typical or atypical antipsychotics would be best for their situation.

3. Behavioral Modifications


  • Daily routines
  • Good sleep hygiene

Sometimes non-medicated changes can make a big difference.

Keeping a regular daily routine, for example, can help many people with dementia. This routine brings people the comfort of familiarity, which could in turn reduce the stress and confusion that leads to sundowning.

According to the National Institute on Aging (NIH), practicing good sleep hygiene may also help. These practices can include having the person go to bed early, not drinking caffeine later in the day, and not taking long naps.

Why do these simple changes seem to work for many people? According to the Alzheimer’s Association, it may be due to the fact that AD can affect the brain. These changes may cause issues like mental and physical tiredness, which can trigger sundowning. Activities that improve sleep may therefore reduce the odds of sleep disturbances and other triggers that contribute to late-day confusion.

4. Light Therapy

Also called:

  • Phototherapy

Light therapy is a therapy that involves exposure to sunlight or another light form. Some use it to treat conditions like seasonal affective disorder or certain circadian rhythm disorders. In these cases, experts believe that light therapy helps reset the body’s internal clock, which regulates the sleep-wake cycle. In turn, this reset may improve mood or sleep quality.

A few studies show that treatment involving light therapy may help reduce restlessness and improve sleep quality for people living with dementia. These improvements might reduce the incidence of sundowning.

5. Melatonin Supplements

Melatonin is a hormone that helps regulate the sleep-wake cycle. That is why oral melatonin supplements are often a go-to treatment for short-term insomnia. Some research suggests that treatments involving melatonin may improve sleep quality and reduce sundowning behavior for people with dementia.

While melatonin is a common over-the-counter supplement, people should still discuss with their doctors whether using it is the right option for managing their specific condition.

Final Thoughts

For people with loved ones experiencing sundown syndrome, it’s important to know that there are treatment methods available that can help bring their loved ones comfort. From managing medications to practicing good sleep hygiene, there are plenty of options to discuss with a doctor that can provide relief and improve quality of life.

Disclaimers – This article does not constitute professional, legal, medical, healthcare, or financial advice. This article is for informational or educational purposes only and has not been fact-checked by a licensed medical provider.