Sundowning: A Neurological Syndrome

Sundowning syndrome, or sundowning effect, primarily results in neurocognitive and behavioral changes occurring later in the day.  This is frequently observed in patients with brain-related neurological conditions such as dementia, traumatic brain injury, brain tumors, metabolic disturbances, or other neurological conditions.  Not only is this condition stressful for patients, but it also affects caregivers and healthcare professionals.

While sundowning is not totally understood, a number of factors may influence the onset and persistent nature of this syndrome.  It is considered a multifactorial syndrome based on physiological, neurobiological, pharmacological, environmental, and medical components.  For example, specific elements considered to be a contributing factor to sundowning include medications, a patient’s history of a sleep disorder, brain-related physical changes (e.g., changes in melatonin, neurotransmitters, glucose, circadian rhythms) as well as environmental considerations (e.g., change in environment, overstimulation, reduced sunlight).  Individuals are particularly prone for developing sundowning when they are overstimulated and experience both physical and neurocognitive exhaustion.  At that time, individuals have difficulty and a lack of tolerance when placed in an unfamiliar, ever-changing, and often misperceived threatening environment.

Sundowning syndrome is generally considered, and eventually diagnosed, through patient observation.  As previously discussed, these individuals have a tendency toward increased confusion and behavioral changes (e.g., restlessness, agitation, disorientation) later in the day or when the sun goes down, hence the term sundowning.  Sundowning may also occur in individuals with other coexisting conditions such as depression, anxiety, urinary tract infections, pain symptoms, and documented sleep disturbances such as chronic obstructive sleep apnea.

Once sundowning is formally and clinically diagnosed, treatment strategies can be enforced.  First and foremost, an individuals prescribed an over-the-counter medication regimen needs to be identified and assessed.  It is imperative that specific medications be avoided to minimize an adverse medication interaction effect which often heightens an individual’s level of confusion and behavioral decompensation.  Despite this, some medications may prove beneficial in ameliorating some of the adverse symptoms.  Environmental changes can also prove beneficial, which may include keeping individuals in a familiar and non-threatening environment, minimize over-stimulation, increase light exposure, including fluorescent bulbs, and aromatherapy (e.g., in particular, lavender oils have proved to be both calming and relaxing).

From a preventive perspective, preventing or minimizing sundowning syndrome or sundowning effect is imperative.  The successful implementation of the following strategies often proves beneficial:

  • Doctors’ appointments or daily therapeutic interventions should be scheduled in the morning or early afternoon.
  • Maintain a regular morning and bedtime routine.
  • Expose the individual to as much natural lightening as possible throughout the day.
  • Provide the individual with a larger meal in the afternoon and a smaller meal at night.
  • Keep a daily log as to what activities may increase confusion or adverse behavioral changes and those activities which appear beneficial in reducing sundowning.

In summary, while sundowning syndrome or sundowning effect often occurs in individuals with a host of neurological conditions, understanding the symptoms, causes, and preventive measures is paramount.   While sundowning is stressful to the patient, caregivers, and healthcare professionals, utilizing some of the aforementioned information and treatment strategies will undoubtedly be helpful.  If you or other individuals are exposed to this challenging situation and in need of additional information or clinical consultation, please do not hesitate to contact us at 732-988-3441.


Michael J. Raymond, Ph.D., ABN, FACPN
Board Certified Neuropsychologist #232
Licensed Psychologist #35S100252900