Synopsis
Formulate distress and behaviour in dementia through unmet need and delirium assessment, use antipsychotics only within strict risk criteria, and apply decision-specific Mental Capacity Act practice.
- Describe the behaviour precisely—who, when, where, trigger, duration and consequence—rather than using 'challenging behaviour' as a diagnosis.
- Before treatment perform a structured assessment for pain, delirium, infection, hunger, thirst, constipation, urinary retention, sleep, sensory loss, environment and communication.
- Offer psychosocial and environmental interventions first when there is no emergency, matching meaningful activity, routine, lighting, noise and carer approach to the person.
- Antipsychotics are considered only when the person is at risk of harming themselves or others, or has agitation, hallucinations or delusions causing severe distress.
- Use the lowest effective antipsychotic dose for the shortest possible time, reassess at least every 6 weeks and stop if there is no clear ongoing benefit.
- People with dementia with Lewy bodies or Parkinson disease dementia can have severe antipsychotic sensitivity with rigidity, sedation, autonomic collapse or neuroleptic malignant syndrome.
- Capacity is presumed and is specific to the decision and time; a dementia diagnosis, eccentric choice or poor memory score does not establish incapacity globally.
- A person lacks capacity only when an impairment of mind or brain means they cannot understand, retain, use or weigh relevant information, or communicate the decision despite practicable support.
- Best-interests decisions consider the person's wishes, values and relevant others, exclude convenience or age-based assumptions and choose the least restrictive effective option.
Key red flags
Acute fluctuating attention, altered arousal, sleep-wake reversal or new perceptual symptoms over hours to days indicates urgent delirium assessment even with established dementia.
Marked rigidity, reduced consciousness, autonomic instability or fever after an antipsychotic in Lewy body or Parkinson dementia is an emergency toxicity signal.
A superficially coherent decision made under pressure, fear or exploitation requires private assessment and safeguarding rather than assuming either capacity or incapacity resolves coercion.
Investigation priorities
Find acute illness, pain and physiological causes behind new behavioural change.
Management branches
Distress, agitation, wandering, resistance or perceptual symptoms emerge or worsen.
- Define onset and behaviour precisely, assess immediate harm and perform urgent delirium, pain, retention, constipation, infection and medicine review.
- Ask what happens immediately before and after episodes, including staff language, personal-care task, noise, lighting, hunger and sensory access.
- Co-design routine, meaningful activity, communication, comfort and environmental changes with family and care staff, documenting what de-escalates distress.
- Measure response and reconsider diagnosis before psychotropic escalation, maintaining emergency safeguards when serious harm is imminent.