A practical guide for carers
Seeing or hearing things that are not there can be unsettling, both for the person living with dementia and for those supporting them. It can raise concerns about what is happening and what to do next.
Understanding the possible causes can help you respond with confidence and know when to seek further support.
What are hallucinations?
A hallucination is when a person sees, hears, smells, tastes, or feels something that is not physically present.
In dementia, hallucinations are more commonly associated with Dementia with Lewy bodies, but they can also occur in Alzheimer’s disease and other types of dementia, particularly as the condition progresses.
Sometimes what looks like a hallucination may actually be:
- A delayed response to a previous conversation
- Confusion about who is present
- A vivid memory being experienced as if it is happening now
- Misinterpretation of the environment (such as shadows, reflections, or background noise)
For example, if family members have recently visited, the person may be revisiting that interaction and speaking it aloud later. Dementia can affect how the brain processes time and sequencing, meaning past and present experiences can become blurred.
Other possible causes to consider
It is important not to assume it is “just the dementia.” Sudden or increased hallucinations can sometimes be linked to underlying physical or environmental factors.
- Infection (particularly urinary tract infections)
- Dehydration
- Pain or discomfort
- Medication changes or side effects
- Constipation
- Poor sleep
- Changes in routine or emotional stress
- Reduced hearing or vision
If the experiences are new, worsening, or accompanied by changes in behaviour, it is advisable to contact the GP to rule out physical causes.
When to seek urgent medical advice
A sudden change (over hours or days), especially if there is unusual drowsiness, agitation, fever, or reduced eating and drinking, may indicate delirium and requires urgent medical attention.
Could it be sundowning?
Some people experience increased confusion later in the day. This is often referred to as “sundowning.” It describes a pattern some people with dementia experience, not a diagnosis in itself.
Signs may include:
- More confusion in the late afternoon or evening
- Increased agitation or restlessness
- Talking to people who are not there
- Sleep disruption
Noticing when these changes occur can help identify patterns.
Keeping a simple record
It can be helpful to keep a brief diary for one to two weeks. This does not need to be detailed, just enough to notice patterns.
- Date and time
- What was happening beforehand
- Who was present
- What was said or done
- How long it lasted
- How it resolved
- Any physical changes (pain, temperature, eating, drinking, toileting)
Patterns often emerge, such as time of day, fatigue, certain topics, or environmental triggers.
How to respond in the moment
If the person believes they are speaking to someone who is not there:
- Stay calm and respond to the emotion rather than correcting the fact
- Avoid arguing or insisting they are wrong
- Offer reassurance
- Gently redirect if needed
- Check the environment (lighting, shadows, background noise)
If the experience is not causing distress, it may not need to be challenged at all. The key question is whether the person appears frightened or upset.
A note of reassurance
Hallucinations can be unsettling, but they are not uncommon in dementia. They do not automatically mean rapid decline or a change in diagnosis.
The most important steps are:
- Ruling out physical causes
- Looking for patterns
- Supporting the person emotionally
- Making sure you feel supported too
If you are supporting someone at home and would find it helpful to talk things through with others in a similar situation, Young At Heart ULO CIC offer peer support sessions that are open to family carers. Details are on the website.
Useful resources
- Alzheimer’s Society: Hallucinations and dementia
- Dementia UK: Changes in perception
- NHS: Dementia symptoms and support
Want to learn more?
Our Understanding Challenging Behaviour training covers hallucinations alongside a range of behaviours that can be difficult to interpret or respond to. It is designed for anyone supporting a person living with dementia, whether at home or in a care setting.