Evening Syndrome: Symptoms, Causes and Treatment

Evening syndrome, also called twilight syndrome or sundowning syndrome, involves episodes of agitation, irritation, and confusion in the early afternoon. It usually appears in people with Alzheimer's disease. Get to know its symptoms, causes and treatments.
Evening Syndrome: Symptoms, Causes and Treatment
Laura Ruiz Mitjana

Written and verified by la psicóloga Laura Ruiz Mitjana.

Last update: 04 April, 2021

Evening syndrome is a disorder that appears mostly in people with Alzheimer’s disease. It starts in the early evening or at the time of going to sleep. It is characterized by symptoms such as irritation, agitation, confusion, and behavioral disorder.

Also called twilight syndrome, sundown syndrome or sundowning, it can be very unpleasant to live through, both for the patient and for their families. Among its causes, we find a possible alteration or deficit in the person’s circadian rhythm or biological clock, which would be in charge of regulating an adequate cycle of sleep and wakefulness.

“Twilight is a daily failure of nature.”

-Enrique Jardiel Poncela-

The treatment of the syndrome is focused on reducing the symptoms, through drugs and especially measures that promote a peaceful and restful sleep (sleep hygiene), as well as healthy lifestyle habits. Regulating and adjusting lighting and other environmental factors can also help.

On the other hand, emotional support and patient support will also be key elements in this syndrome.

Evening syndrome: what is it?

Evening syndrome affects older people.
This condition not only greatly affects patients, but also caregivers.

According to the residential psychologist Ángel Moreno, in a 2007 study, evening syndrome is one of the most common phenomena in geriatric medicine, and can be defined as a psychological-behavioral adverse event, which appears especially in people with the disease of Alzheimer’s.

It has been shown that these people become very restless, aggressive, and agitated in the late afternoon and during the evening. This syndrome causes a period of extreme agitation and irritation that begins during the late afternoon or evening. More specifically, it occurs in the early evening and usually lasts until night.

Typical in Alzheimer’s

It affects up to 20% of people with Alzheimer’s, as claimed by the Chicago Alzheimer’s Association through various studies.

Patients who are in the intermediate stage of the disease are more likely to develop it. The main cause of it seems to be a dysfunction of the circadian rhythm, which is the internal biological clock that we all have and that’s responsible for regulating the sleep and waking cycles.


The two main symptoms of evening syndrome are agitation and confusion. However, to these symptoms we can add others, the most frequent being:

  • Ambulatory behavior
  • Disorientation and bewilderment (the person doesn’t know where they are)
  • Attempts at self-harm
  • Throwing objects compulsively
  • Screaming (directed at themselves or others)
  • Trying to tear their clothes
  • High activity at night
  • Sleep or drowsiness during the day
  • Various behavioral disorders

Experts know that, at dusk, many people with Alzheimer’s believe that “the time has come” to go home. This would imply the appearance of some of the symptoms we’ve mentioned.

On the other hand, there are other factors that could increase the probability of the appearance of some symptoms that are closely related to this disorder’s etiology (as we will see later). Among them we find:

  • A lack of ambient light (or inadequate light, poor lighting)
  • Increased darkness
  • Have an underlying infection
  • Sudden environmental and environmental changes
  • Mental and/or physical exhaustion (fatigue)
  • A feeling of loneliness, and of being away from loved ones

How does the person with evening syndrome behave?

Evening syndrome is a difficult and complex disorder because it creates a lot of suffering and discomfort for the person, who feels very confused. Caregivers and family members also suffer the consequences of it.

So, we have seen some of the common symptoms of the syndrome, but how does a person with the disorder behave in general?

According to the aforementioned study carried out by Moreno (2007), at an expressive level patients with the evening syndrome can exhibit a reserved monologue, animated arguments, shouting, cursing, and outbursts.

Through this behavior, they constantly request the caregiver’s attention, repeatedly reproducing certain gestures and complaints.

On the other hand, the patient’s confusion and disorientation will lead to a state of anxiety and fear, which expresses itself through symptoms such as anger and irritability, and which alternates with moments of apathy and depression. In addition, headaches and perceptual disorders may appear.


The main cause associated with evening syndrome is an alteration in circadian rhythms. These rhythms are regulated by a brain structure called the suprachiasmatic nucleus, where melatonin (the main sleep hormone) plays a major role.

In people suffering from Alzheimer’s, this structure is damaged, which implies a decrease in the production of melatonin. The consequences of this are alterations in the internal biological clock, which would cause confusion when sleeping and waking up,

In the etiology of evening syndrome, we also find other factors involved, such as environmental changes, mental and physical fatigue (fatigue), poor lighting, and other diseases that would cause discomfort and pain in the patient. In more detail, in relation to its causes we find the following:

  • Physical and mental exhaustion, added to confusion in unfamiliar places and with unfamiliar people, can intensify symptoms.
  • A tense environment can cause and worsen symptoms.
  • Poor lighting can lead to shadows and increase the confusion of the person, who becomes more and more agitated.

Treatment: general measures

Evening syndrome requires medical support.
Medical and psychological support can improve the quality of life of these patients.

In the treatment of evening syndrome, different types of measures are used: environmental, nutritional, pharmacological, medical, and psychological. Some techniques that are usually applied to improve this syndrome are the following:

  • Exposing the patient to natural light (and if this isn’t possible, artificial light) in the early hours of the morning in order to regulate their biological clock
  • Reducing environmental noise
  • Choosing to put on relaxing music
  • Transmitting tranquility, security, and calm
  • Preventing the person with Alzheimer’s from sleeping during the day
  • Exercising during the day can promote sleep
  • Eliminating stimulating substances such as caffeine.
  • Following a healthy diet
  • Establishing fixed hours to eat, take medication, carry out activities, etc.
  • Avoiding the unjustified use of drugs
  • Practicing active listening with the patient, and offering emotional support
  • Taking small walks with family members
  • Not subjecting the patient to physical restraints at night
  • Consulting the doctor as to what time is best to take the medication.

Medical treatment and emotional support

Beyond these measures, medical or pharmacological treatment is usually resorted to, which will be personalized in each case. Drugs such as anxiolytics or antidepressants are sometimes used.

At a psychological level, interventions focused on improving the emotional state of the person are optimal, either through cognitive therapy or other theoretical orientations.

Accompany them at all times

Preventing damage will also be an aspect to take into account. The important thing will be that the person doesn’t feel alone during the times of most agitation.

We’re also talking about physically being present with them as they experience these nocturnal episodes. This can make it easier for them to feel better and calmer. In this sense, we must give them space, but also supervise them. It’s better to let them move around rather than avoiding it. Avoiding it can increase their agitation or irritability.

Psychoeducation directed at the patient and their families can be effective in improving the person’s symptoms. This includes detailed information on the syndrome, possible causes, strategies to alleviate their symptoms, among other things.

A complex syndrome with many therapeutic options

Evening syndrome, as we’ve been able to see throughout the article, is a condition that can considerably worsen the quality of life of the patient and their caregivers.

Consulting the corresponding medical or psychological service early on, and in a responsible way, can help to prevent many complications derived from the disease.

  • Benarroch, E. E. (2008). Suprachiasmatic nucleus and melatonin Reciprocal interactions and clinical correlations. Neurology, 71(8): 594-598.
  • Caballo (2002). Manual para el tratamiento cognitivo-conductual de los trastornos psicológicos. Vol. 1 y 2. Madrid. Siglo XXI.
  • Evans, L.K. (1987). Sundown syndrome in institutionalized elderly. J Am Geriatr Soc, 35:101–108.
  • Miniziniak, H. (1994) Persons with Alzheimer´s: Effects of nutrition and exercise. Journal of Gerontological Nursing, 20 (10): 27-32.
  • Moreno, A. (2007). Correlatos de incidencia del ocaso en estados anímicos, agitación y conducta agresiva en ancianos: Síndrome de Sundowning. SINTITUL-5: 72-80.

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