Sundowning, Aggression and Hallucinations in Dementia: What to Do

Why Behaviour Changes Happen

Dementia doesn't just affect memory. As the condition progresses, it damages the parts of the brain that regulate mood, perception, and impulse control. The person your parent was hasn't chosen to become aggressive or fearful — their brain is processing the world differently, and their behaviour is a response to confusion, discomfort, or distress they often can't articulate.

Understanding this doesn't make it easier to cope with, but it changes how you respond. These aren't problems to fix through reasoning or persuasion — they're symptoms to manage through environment, routine, and communication.

Sundowning: Late-Afternoon and Evening Agitation

Sundowning refers to a pattern of increased confusion, anxiety, agitation, and sometimes aggression that begins in the late afternoon and continues into the evening. It affects up to two-thirds of people with moderate to advanced dementia.

What triggers it:

• Fatigue — cognitive reserves are depleted by the end of the day
• Low light — shadows and dimming rooms create visual confusion
• Internal body clock disruption — dementia damages the circadian rhythm
• Unmet needs — hunger, thirst, pain, or a full bladder that the person can't communicate
• Overstimulation — a busy household during the after-school or after-work rush

What helps:

• Brighten the room before dusk. Turn on lights early so there's no visible transition from daylight to artificial light. Close curtains to eliminate shadows
• Keep a consistent late-afternoon routine. A familiar activity at the same time each day — folding laundry, looking through photo albums, listening to music from their younger years — provides structure during the vulnerable hours
• Offer a snack and drink. Hunger and dehydration can exacerbate agitation. A cup of tea and a biscuit at 4pm can prevent an episode at 6pm
• Reduce stimulation. Turn off the television if it's adding noise without engagement. Lower the household energy level
• Don't argue or correct. If your parent insists it's morning or that they need to go to work, go with it. Redirect rather than contradict
• Check for pain. Arthritis, dental problems, constipation, and urinary infections all worsen in the evening when distraction fades. A person with dementia may express pain as agitation because they can't locate or describe the discomfort

Aggression: Physical and Verbal

Aggressive behaviour — shouting, swearing, hitting, pushing, grabbing — is deeply distressing for families. It is almost always a response to something, not an unprovoked act.

Common triggers:

• Feeling rushed or forced during personal care (bathing, dressing, toileting)
• Invasion of personal space by someone the person doesn't recognise
• Frustration at being unable to do something they used to manage easily
• Fear or confusion about where they are or what's happening
• Pain that they can't communicate verbally

How to respond in the moment:

• Stay calm and keep your voice low and steady
• Don't restrain unless there's an immediate safety risk
• Step back and give space — leave the room briefly if you can do so safely
• Don't take it personally. The aggression is directed at the situation, not at you
• Try again later. If bathing triggered it, come back in twenty minutes with a different approach — a warm flannel wash instead of a full bath, for example

When to seek medical help:

If aggressive episodes are new, sudden, or dramatically worse, see the GP. A urinary tract infection, constipation, or medication side effect can cause rapid behavioural changes in someone with dementia. Treating the underlying cause often resolves the aggression.

Antipsychotic medications are sometimes prescribed for severe behavioural symptoms, but they carry significant risks for people with dementia — including increased stroke risk and faster cognitive decline. They should be a last resort after environmental and non-pharmacological approaches have been tried.

Hallucinations: Seeing and Hearing Things That Aren't There

Visual hallucinations are particularly common in Lewy body dementia but can occur in all types. Your parent may see people, animals, or objects that aren't present. Auditory hallucinations (hearing voices or sounds) are less common but do occur.

How to respond:

• Don't dismiss what they're experiencing. Saying "there's nothing there" contradicts their reality and causes distress. Instead, acknowledge their experience: "That sounds frightening. You're safe here with me"
• Check for simple explanations first. Reflections in mirrors or windows, patterns in curtains, a coat hanging on a door — all of these can be misinterpreted by a brain processing visual information poorly
• Don't play along if it increases distress. There's a balance between validating feelings and reinforcing a frightening hallucination. If your parent sees a stranger in the room and is scared, reassure them rather than pretending to see the stranger too
• Adjust the environment. Cover mirrors if they cause confusion. Improve lighting to reduce shadows. Remove patterned wallpaper or busy furnishings that can be misinterpreted

When hallucinations need medical attention:

If hallucinations are causing significant distress, leading to dangerous behaviour (running from the house, becoming aggressive toward an imagined threat), or are a new symptom, contact the GP or memory clinic. For Lewy body dementia, specific medications can help — but the wrong medications (certain antipsychotics) can cause severe adverse reactions.

Getting Support

Managing behavioural changes is the aspect of dementia care that drives carer burnout most acutely. The 96% of carers who report being "always on alert" are largely describing the vigilance required to manage unpredictable behaviour.

Our Dementia Care in England guide covers behavioural management strategies alongside the practical and legal aspects of dementia care — from daily care diaries that help you track triggers through to guidance on requesting a carer's assessment for yourself.

See more England guides →