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Behavioral and Psychologic Symptoms of Dementia


Juebin Huang

, MD, PhD, Department of Neurology, University of Mississippi Medical Center

Last full review/revision Mar 2021| Content last modified Mar 2021

Disruptive actions are common among patients with dementia and are the primary reason for up to 50% of nursing home admissions. Disruptive actions include wandering, restlessness, yelling, throwing, hitting, refusing treatment, incessantly questioning, disrupting work of staff members, insomnia, and crying. Behavioral and psychologic symptoms of dementia have not been well characterized, and their treatment is poorly understood.

Deciding what actions constitute a behavioral symptom is highly subjective. Tolerability (what actions caregivers can tolerate) depends partly on the patient’s living arrangements, particularly safety. For example, wandering may be tolerable if a patient lives in a safe environment (with locks and alarms on all doors and gates); however, if the patient lives in a nursing home or hospital, wandering may be intolerable because it disturbs other patients or interferes with the operation of the institution.

Many behaviors (eg, wandering, repeatedly questioning, being uncooperative) are better tolerated during the day. Whether sundowning (exacerbation of disruptive behaviors at sundown or early evening) represents decreased tolerance by caregivers or true diurnal variation is unknown. In nursing homes, 12 to 14% of patients with dementia act disruptively more often during the evening than during the day.

(See also Overview of Delirium and Dementia and Dementia.)


Behavioral and psychologic symptoms may result from functional changes related to dementia:

  • Reduced inhibition of inappropriate behaviors (eg, patients may undress in public places)
  • Misinterpretation of visual and auditory cues (eg, they may resist treatment, which they perceive as an assault)
  • Impaired short-term memory (eg, they repeatedly ask for things already received)
  • Reduced ability or inability to express needs (eg, they wander because they are lonely, frightened, or looking for something or someone)

Patients with dementia often adapt poorly to the regimentation of institutional living. Mealtimes, bedtimes, and toileting times are not individualized. For many older patients with dementia, behavioral and psychologic symptoms develop or worsen after they are moved to a more restrictive, unfamiliar environment.

Physical problems (eg, pain, shortness of breath, urinary retention, constipation, physical abuse) can exacerbate behavioral and psychologic symptoms partly because patients may be unable to adequately communicate what the problem is. Physical problems can lead to delirium, and delirium superimposed on chronic dementia may worsen the behavioral symptom.


  • Characterization of behaviors (eg, by Cohen-Mansfield Agitation Inventory)
  • Recording of specific behaviors
  • Evaluation for coexisting depression and psychosis

The best approach is to characterize and classify the behavior, rather than to label all such behaviors agitation, a term with too many meanings to be useful. The Cohen-Mansfield Agitation Inventory is commonly used; it classifies behaviors as follows:

  • Physically aggressive: For example, hitting, pushing, kicking, biting, scratching, or grabbing people or things
  • Physically nonaggressive: For example, handling things inappropriately, hiding things, dressing or undressing inappropriately, pacing, repeating mannerisms or sentences, acting restless, or trying to go elsewhere
  • Verbally aggressive: For example, cursing, making strange noises, screaming, or having temper outbursts
  • Verbally nonaggressive: For example, complaining, whining, constantly requesting attention, not liking anything, interrupting with relevant or irrelevant remarks, or being negative or bossy

The following information should be recorded:

  • Specific behaviors
  • Precipitating events (eg, feeding, toileting, drug administration, visits)
  • Time the behavior started and resolved should be recorded

This information helps identify changes in pattern or intensity of a behavior and makes planning a management strategy easier.

If behavior changes, a physical examination should be done to exclude physical disorders and physical abuse, but environmental changes (eg, a different caregiver) should also be noted because they, rather than a patient-related factor, may be the reason.

Depression, common among patients with dementia, may affect behavior and must be identified. It may first manifest as an abrupt change in cognition, decreased appetite, deterioration in mood, a change in sleep pattern (often hypersomnolence), withdrawal, decreased activity level, crying spells, talk of death and dying, sudden development of irritability or psychosis, or other sudden changes in behavior. Often, depression is suspected first by family members.

Psychotic behavior must also be identified because management differs. Presence of delusions or hallucinations indicates psychosis. Delusions and hallucinations must be distinguished from disorientation, fearfulness, and misunderstanding, which are common among patients with dementia:

  • Delusions without paranoia may be confused with disorientation, but delusions are usually fixed (eg, a nursing home is repeatedly called a prison), and disorientation varies (eg, a nursing home is called a prison, a restaurant, and a home).
  • Hallucinations occur without external sensory stimuli; hallucinations should be distinguished from illusions, which involve misinterpreting external sensory stimuli (eg, cellular phones, pagers).


  • Environmental measures and caregiver support
  • Drugs only when necessary

Management of behavioral and psychologic symptoms of dementia is controversial and has been inadequately studied. Supportive measures are preferred; however, drugs are commonly used.

Environmental measures

The environment should be safe and flexible enough to accommodate behaviors that are not dangerous. Signs to help patients find their way and doors equipped with locks or alarms can help ensure the safety of patients who wander. Flexible sleeping hours and organization of beds can help patients with sleeping problems.

Measures used to treat dementia generally also help minimize behavioral symptoms:

  • Providing cues about time and place
  • Explaining care before giving it
  • Encouraging physical activity

If an institution cannot provide an appropriate environment for a particular patient, transferring the patient to one that can may be preferable to drug treatment.

Caregiver support

Providing caregiver support is crucial.

Learning how dementia leads to behavioral and psychologic symptoms and how to respond to disruptive behavior can help family members and other caregivers provide care for and cope with the patient better.

Learning how to manage stress, which may be considerable, is essential. Stressed caregivers should be referred to support services (eg, social workers, caregiver support groups, home health aides) and should be told how to obtain respite care if such care is available.

Family members who are caregivers should be monitored for depression, which occurs in nearly half of them. Depression in caregivers should be treated promptly.

Use of drugs

Drugs that improve cognition (eg, cholinesterase inhibitors) may also help manage behavioral and psychologic symptoms in patients with dementia. However, drugs directed primarily at behavior (eg, antipsychotics) are used only when other approaches are ineffective and when drugs are essential for safety. The need for continued treatment should be reassessed at least every month. Drugs should be selected to target the most intolerable behaviors.

Antidepressants, preferably selective serotonin reuptake inhibitor (SSRIs), should be prescribed only for patients with signs of depression.


Antipsychotics are often used even though their efficacy has been shown only in psychotic patients. Other patients are unlikely to benefit and are likely to experience adverse effects, particularly extrapyramidal symptoms. Tardive dyskinesia or tardive dystonia may develop; these conditions often do not resolve when the dose is reduced or the drug is stopped.

Choice of antipsychotic depends on relative toxicity. Of conventional antipsychotics, haloperidol is relatively nonsedating and has less potent anticholinergic effects but is most likely to cause extrapyramidal symptoms; thioridazine and thiothixene are less likely to cause extrapyramidal symptoms but are more sedating and have more anticholinergic effects than haloperidol.

Second-generation (atypical) antipsychotics (eg, aripiprazole, olanzapine, quetiapine, risperidone) are minimally anticholinergic and cause fewer extrapyramidal symptoms than conventional antipsychotics; however, these drugs, used for an extended period, may cause weight gain and hyperlipidemia and increase the risk of type 2 diabetes. In older patients with dementia-related psychosis, these drugs may increase the risk of stroke and death.

If antipsychotics are used, they should be given in a low dose (eg, olanzapine 2.5 to 15 mg orally once a day; risperidone 0.5 to 3 mg orally every 12 hours; haloperidol 0.5 to 1.0 mg orally, IV, or IM twice a day or as needed) and for a short time.

Other drugs

Antiseizure drugs, particularly valproate, may be useful in controlling impulsive behavioral outbursts.

Sedatives (eg, a short-acting benzodiazepine such as lorazepam 0.5 mg orally every 12 hours as needed) are sometimes used in the short term to alleviate event-related anxiety, but such treatment is not recommended for the long term.

Key Points

  • What constitutes disruptive behavior is subjective and variable, yet behavioral disturbances are the reason for up to 50% of nursing home admissions.
  • Behavior often deteriorates when patients are moved from their familiar home environment.
  • Behavioral disturbances may be triggered by a physical problem that the patient cannot communicate.
  • Categorize behavioral disturbances using the Cohen-Mansfield Agitation Inventory.
  • Recognize signs of depression, such as abrupt changes in cognition, decreased appetite, deterioration in mood, a change in sleep pattern (often hypersomnolence), withdrawal, decreased activity level, crying spells, and talk of death and dying, and be alert for sudden development of irritability o psychotic behavior.
  • Treat using environmental measures, avoiding drugs when possible.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • BPSD Algorithm: This tool aims to help provide interdisciplinary, evidenced-based care for patients with behavioral and psychologic symptoms caused by dementia. It provides guidance for evaluation and use of drugs, as well as a flow chart.

Drugs Mentioned In This Article

Drug Name Select Trade
thioridazine No US brand name
aripiprazole ABILIFY
thiothixene NAVANE
risperidone RISPERDAL
haloperidol HALDOL
olanzapine ZYPREXA
quetiapine SEROQUEL
lorazepam ATIVAN

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