Red flags
- Acute/subacute onset or fluctuation -> delirium until proven otherwise
- New focal neurology -> stroke, subdural
- Fever, tachycardia, hypoxia -> sepsis, PE
- Severe agitation with self/other harm risk
- Rapid progression over days-weeks (not typical BPSD tempo)
- Unrelieved pain behaviour (grimacing, guarding) - occult fracture, retention, impaction
Differential by mechanism
- Delirium (infection, drugs, metabolic, pain, constipation, urinary retention)
- Undertreated pain
- Substance withdrawal (EtOH, benzodiazepine)
- Structural - subdural, stroke, raised ICP
- Depression with agitation ("depressive pseudo-BPSD")
- Late-onset psychosis
- Anxiety
- Agitation/aggression, wandering, disinhibition, apathy, psychosis (hallucinations, misidentification)
- Sundowning
- Differs by dementia subtype - Lewy body: visual hallucinations + fluctuation early; FTD: disinhibition, apathy predominate over memory
Focused history
- Onset and tempo - acute (delirium) vs gradual (BPSD progression)
- ABC charting - Antecedent / Behaviour / Consequence, time of day pattern
- Collateral - carer/family/nursing home report, baseline cognition
- Pain, bowel/bladder function, sleep
- Medication changes - new anticholinergics, opioids, steroids, sedative withdrawal
- Psychiatric history, past response to agents
- Environmental triggers - room change, unfamiliar staff, overstimulation
Focused examination
- Vital signs, hydration, signs of infection
- Abdominal exam - constipation, retention (bladder scan)
- Skin - pressure areas, occult injury
- Neurological - focal signs, parkinsonism (caution: antipsychotic sensitivity in Lewy body)
- Cognitive screen if not already established (MMSE/MoCA), delirium screen (4AT/CAM)
- Pain assessment tools if non-verbal (Abbey Pain Scale, PAINAD)
Investigation strategy
- Delirium screen: FBE, UEC, CRP, glucose, calcium, TFTs, LFTs, MSU, CXR +/- septic screen
- Medication review - anticholinergic burden, recent additions
- CT brain if new focal signs, fall with head strike, anticoagulated, rapid progression
- Avoid reflexive neuroimaging in known stable dementia without new signs
Management
1. Treat reversible cause - infection, pain, constipation, retention, drug effect, hunger/thirst, environment
2. Non-pharmacological first-line - person-centred approach, consistent routine/staff, reduce overstimulation, redirect rather than confront, involve family, validate emotion not content of delusion
3. Pharmacological - only if severe distress or safety risk, non-pharm failed/inadequate
- Risperidone - only PBS-subsidised/TGA-approved antipsychotic for BPSD; short-term use only, lowest dose, regular review for cessation
- Black-box warning: inc stroke and mortality risk in dementia-related psychosis
- Avoid antipsychotics in Lewy body/Parkinson's dementia - severe neuroleptic sensitivity
- If unavoidable: quetiapine lowest dose
- Avoid benzodiazepines - worsen confusion, falls, paradoxical disinhibition; short-acting only for acute severe crisis
- Trial cessation regularly - antipsychotics for BPSD are time-limited, not maintenance
- Carer education, respite, Dementia Support Australia (Severe Behaviour Response Teams)
Traps
- Treating BPSD as a diagnosis rather than screening for delirium/pain first
- Antipsychotic use in Lewy body dementia -> severe sensitivity reaction
- Long-term antipsychotic continuation without cessation trial
- Physical restraint - increases agitation, injury risk, no evidence of safety benefit
- Assuming non-verbal distress is "just dementia" rather than pain or delirium
Talk track
Acute/fluctuating change in behaviour = delirium first - exclude infection, pain, constipation, retention, drugs. If genuine BPSD: non-pharmacological strategies first (routine, redirection, environment), pharmacotherapy only for severe risk/distress with regular cessation review - risperidone is the only approved agent, avoided in Lewy body dementia due to neuroleptic sensitivity.
8 of 8 sections written · drafted 2026-09-13