Behavioural and psychological symptoms of dementia

At a glance

• Up to 90% of people with dementia have behavioural or psychological symptoms at some stage. Apathy is the commonest; agitation and aggression cause the most distress, carer breakdown and admissions to residential care.
• Behaviour is usually communication. Look for pain, delirium, constipation, retention, fear and unmet needs before reaching for a drug.
• Non-drug approaches are first line for everything except imminent danger or distressing psychosis.
• Antipsychotics give a small benefit for aggression and psychosis only, and increase stroke and death. Use the lowest dose, for the shortest time, with a stop date.
• In residential aged care, a medicine used mainly to influence behaviour is chemical restraint under the Aged Care Act 2024, with consent and documentation rules.
• The dementia syndromes, cholinesterase inhibitors and driving are covered in Dementia syndromes.

Symptom clusters

Cluster	Examples	Notes
Agitation and aggression	Pacing, restlessness, hitting, shouting, resisting care	Often triggered by personal care, noise or pain
Psychosis	Delusions of theft or infidelity, misidentification (Capgras), hallucinations	Well-formed visual hallucinations early suggest Lewy body disease
Mood	Depression, anxiety, tearfulness	Use the Cornell Scale for Depression in Dementia; self-report scales fail in moderate dementia
Apathy	Withdrawal, loss of initiative	Often mistaken for depression; doesn't respond to antidepressants
Disinhibition	Sexual comments or touching, impulsivity	Prominent in frontotemporal dementia
Sleep and circadian	Night waking, sundowning	Worse with daytime napping, poor light, nocturia
Repetitive or motor	Wandering, calling out, hoarding, shadowing the carer	Drugs don't help these

Causes

Ask what has changed for this person in the last days to weeks.

• Physical: pain (arthritis, fracture, dental, pressure injury), delirium from infection or drugs, constipation, urinary retention, hypoxia, hypoglycaemia, hunger, thirst, sleep deprivation.
• Drugs: anticholinergics, opioids, benzodiazepines (paradoxical agitation), levodopa and dopamine agonists, steroids, recent withdrawal of a long-standing benzodiazepine or antidepressant.
• Sensory: glasses or hearing aids missing, poor lighting.
• Environment: a move, a new carer, a noisy shared room, a busy emergency department, unfamiliar faces.
• Interaction: rushed personal care, being corrected or argued with, carers speaking over the person.
• Psychological: depression, anxiety, boredom, loneliness, loss of a spouse.
• Progression of the dementia itself, a diagnosis reached once the rest is excluded.

Pitfall: new behaviour in hospital is delirium superimposed on dementia until proven otherwise. Check attention against baseline and look for the cause.

Focused history

• Describe the behaviour precisely with the carer or staff: what, when, where, with whom, how often, and what happened just before and after. ABC (antecedent, behaviour, consequence) charts over a few days make patterns visible.
• Who is distressed or at risk? The person, other residents, staff, family. This decides urgency.
• Onset and time course: abrupt change suggests delirium; slow evolution suggests progression or environment.
• Dementia subtype, stage and baseline cognition.
• Pain history from someone who knows the person. Changes in eating, sleeping, bowels and bladder.
• Full medicine list including recent changes and PRN use.
• What has worked before, life history, routines, likes and fears. Carer strain.

Focused examination

• Attention and arousal to look for delirium.
• Observed pain assessment: the Abbey Pain Scale (Australian, for people who can't self-report) or PAINAD. Examine joints, mouth, feet, skin and pressure areas.
• Abdomen and bladder (retention, faecal loading), chest, hydration.
• Parkinsonism, which may point to Lewy body disease or drug effects and matters for antipsychotic choice.
• Vision and hearing.
• Use a structured scale to measure and track symptoms: the Neuropsychiatric Inventory (NPI) or Cohen-Mansfield Agitation Inventory.

Red flags

Situation	Action
Fever, new incontinence, fluctuating alertness	Delirium screen and work-up
Sudden behaviour change after a fall	Look for fracture and subdural haematoma
Imminent risk of serious harm to self or others	Urgent treatment, including short-term medication if de-escalation fails
Suicidal statements, food refusal with weight loss	Assess for severe depression
Severe parkinsonism, rigidity or falls after a dopamine antagonist	Suspect Lewy body disease or neuroleptic sensitivity

Investigations

• Guided by the assessment: FBC, UEC, calcium, glucose, LFTs, TSH, CRP. Urinalysis and culture only with urinary symptoms or sepsis; a positive dipstick alone isn't a cause.
• Bladder scan for retention. Abdominal X-ray only if faecal loading is uncertain.
• CT brain for focal signs, a fall with head strike or unexplained rapid change.
• ECG before an antipsychotic or citalopram (QTc).

Management

The DICE approach (Kales 2015)

1. Describe the behaviour and its context.
2. Investigate causes: physical, drugs, environment, interaction.
3. Create a plan with the carers and the person.
4. Evaluate whether it worked, and adjust.

Non-drug strategies

• Treat the cause: pain, constipation, retention, infection, sensory loss.
• Person-centred care using life history: routines, preferred music, meaningful activity, familiar staff.
• Teach carers to approach calmly from the front, give one instruction at a time, avoid arguing or correcting, and leave and return if care is refused.
• Adjust the environment: lighting, quiet space, daytime activity and light exposure, reduce noise at night.
• Dementia Support Australia (1800 699 799) gives free 24-hour advice and on-site assessment through the Dementia Behaviour Management Advisory Service. Severe Behaviour Response Teams attend residential facilities for severe BPSD, and Specialist Dementia Care Units take people whose behaviour can't be managed in mainstream care.

Analgesia

• A trial of regular paracetamol (1 g up to four times daily, lower in frailty or low body weight) is reasonable when pain is plausible. Husebo (BMJ 2011) showed stepped analgesia reduced agitation in nursing home residents over 8 weeks.
• Low-dose buprenorphine patches are an option if paracetamol fails. Watch for sedation and constipation.

Antipsychotics

Indications: severe agitation, aggression or psychosis causing significant distress or risk of harm, when non-drug approaches have failed or the risk is immediate.

• Risperidone is the only antipsychotic TGA-registered for BPSD: moderate to severe Alzheimer dementia, unresponsive to non-drug approaches, with risk of harm, for up to 12 weeks. The indication covers psychotic symptoms, or persistent agitation or aggression. Start 0.25 mg twice daily, increasing by 0.25 mg twice daily no more often than every second day; the optimum for most is 0.5 mg twice daily, and some need up to 1 mg twice daily (product information).
• Brexpiprazole is TGA-registered for agitation associated with Alzheimer dementia, but not PBS-listed for it.
• Lewy body disease and Parkinson disease dementia: avoid haloperidol and risperidone. Use a cholinesterase inhibitor first, then low-dose quetiapine (or clozapine with specialist input) for distressing psychosis. In Australia cholinesterase inhibitors are PBS-subsidised only for Alzheimer disease, so rivastigmine here is off-label on a private script. Pimavanserin, used for Parkinson disease psychosis in the US, isn't available in Australia.
• Benefit is small: about 1 in 5 to 1 in 14 people improve beyond placebo, and CATIE-AD found no overall advantage once discontinuation for adverse effects was counted.

Harm	Size
Death	About 1.6 to 1.7 times placebo over 10 to 12 weeks (roughly 1 extra death per 100)
Stroke	About tripled with risperidone and olanzapine in trials
Falls and hip fracture	Sedation, orthostatic hypotension, parkinsonism
Other	Pneumonia, VTE, cognitive decline, weight gain, QT prolongation

• Review at 6 to 12 weeks and taper. In DART-AD, residents randomised to continue antipsychotics had higher long-term mortality (about 30% versus 59% alive at 36 months). In the Australian HALT study, most residents stopped antipsychotics without behaviour worsening. The exception is people whose psychosis or agitation responded well to risperidone: in ADARP (Devanand, NEJM 2012) relapse by 16 weeks was 60% after switching to placebo versus 33% on risperidone. Taper slowly and watch for return of symptoms.
• The ACSQHC Psychotropic Medicines in Cognitive Disability or Impairment Clinical Care Standard (2024) expects a documented indication, informed consent, the lowest effective dose, monitoring and a review date for every psychotropic.

Pitfall: PRN antipsychotics charted "for agitation" with no defined target, dose limit or review. They drift into long-term use.

Other drugs

Drug	Evidence and cautions
Citalopram	Reduced agitation in CitAD (30 mg), but prolongs QT; TGA maximum 20 mg daily over 65
SSRIs in FTD	May reduce disinhibition and compulsions
Mirtazapine	No benefit for agitation in SYMBAD (2021), with a mortality signal
Cholinesterase inhibitors	Modest benefit for psychosis and apathy, more in Lewy body disease
Benzodiazepines	Avoid: falls, sedation, paradoxical agitation, worse cognition. Reserve for short-term crisis use
Antidepressants	For coexisting depression, not apathy

Acute severe agitation in hospital

• De-escalate first, with familiar people if possible. Treat delirium causes.
• If medication is needed for safety, use a low oral dose first (for example risperidone 0.25 to 0.5 mg or olanzapine 2.5 mg). Parenteral sedation in older people needs lower doses and monitoring as in Significant behavioural issues.
• Avoid haloperidol if Lewy body disease is possible.

Restrictive practices in aged care

• Under the Aged Care Act 2024 (in force from 1 November 2025), chemical restraint is a medicine used mainly to influence behaviour. A medicine treating a diagnosed mental disorder, a physical illness or end-of-life symptoms isn't restraint.
• Any restrictive practice must be a last resort, the least restrictive option, set out in a behaviour support plan, with informed consent from the person or their restrictive practices substitute decision-maker, then monitored and reviewed.
• Antipsychotic use is a national mandatory quality indicator in residential aged care.

Pitfalls

• Starting an antipsychotic before looking for pain, constipation, retention and delirium.
• Using antipsychotics for wandering, calling out or resisting care, which they don't help.
• Giving haloperidol to someone with undiagnosed Lewy body dementia.
• No stop date. Most people can taper after 12 weeks without relapse, but those whose severe psychosis or agitation responded well relapse more often (ADARP), so taper slowly and monitor.
• Treating apathy with an antidepressant.
• Calling a positive urine dipstick the cause of behaviour change.
• Forgetting consent and documentation requirements for chemical restraint in residential care.