Dementia: changes in behaviour
When the person you love acts in ways you don’t recognise, there is usually a reason. Calm words and a little detective work can ease hard moments.
By the numbers
How common some of these changes are.
Communication that works
Short sentences, kind tone, no arguing. Tap a card for each skill.
Dementia makes it harder to find words, follow long conversations, block out background noise and keep a train of thought. Some people go back to their first language. Small changes in how you speak can prevent a lot of upset.
The Dementia: understanding it guide explains why these changes happen. Here are the core skills caregivers use every day.
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- Approach from the front, make eye contact and use their name
- Say who you are if they may not recognise you
- Turn off the TV or radio and talk one-on-one
- Hold their hand or touch their arm gently if they like it
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Speak slowly and clearly. Ask one question at a time and give plenty of time to answer. Break tasks into single steps and show what you mean.
Try saying this instead
- Instead of “What do you want for dinner?”, try “Fish or chicken?”
- Instead of “That’s not how you do it”, try “Let’s try it this way.”
- Instead of “How do you feel?”, try “Are you feeling sad?”
- Instead of “Are you hungry?”, try “Dinner is ready in five minutes.”
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Look for the meaning and emotion behind the words. If someone is upset because they think they are late for work, the feeling might be worry or wanting to be useful.
Phrases that validate
- “That sounds really worrying.”
- “You’ve always worked so hard.”
- “I’m here. You’re safe with me.”
- “Tell me more about that.”
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Arguing, quizzing (“Don’t you remember?”) or correcting usually makes the person feel embarrassed or frightened. If they say something you disagree with, let it be.
Also avoid
- Talking about the person as if they aren’t there
- Baby talk or a “baby voice”
- Rushing or interrupting
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When a conversation is going badly, change the scene: offer a favourite snack, put on music, look at photos, go for a walk or ask for help with a simple job.
A simple pattern
- Acknowledge: “You really want to go home.”
- Reassure: “I’m here with you.”
- Redirect: “Let’s have a cup of tea first and look at your garden photos.”
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There is no single right answer. The UK’s Alzheimer’s Society suggests choosing what is in the person’s best interest, and being consistent with it.
If someone asks for a parent or partner who has died, hearing the news can feel brand new each time, so they may grieve again and again. Some families share it once, gently, and then respond to the feeling instead: “You’re thinking about your mum. What was she like?”
If they ask to “go home” while at home, don’t argue about where they are. Ask what home means to them, check for hunger, thirst, the bathroom or feeling cold, then offer a walk or photos.
Behaviour is a message
Most changes in behaviour have a cause. Be a calm detective.
Dementia changes the brain, and that can change how a person acts. It is the disease, not the person, causing these changes. Most of the time, agitation or aggression happens for a reason the person can’t put into words.
Common hidden causes
- Pain, tiredness, poor sleep or constipation
- Hunger, thirst or needing the bathroom
- Trouble seeing or hearing
- Too much noise, too many people or a loud TV
- A sudden change in routine, place or caregiver
- Being pushed to do something that has become too hard, like bathing
- Fear, sadness, boredom or loneliness
- A sense of loss, like missing the freedom to drive
The detective steps
- Stay calm and make sure everyone is safe.
- Check the body: pain, hunger, thirst, bathroom, temperature, tight clothes.
- Check the room: noise, crowds, glare, shadows, clutter.
- Think about what happened just before. Was the person rushed, corrected or asked to do too much?
- Respond to the feeling, then redirect.
- Write it down. Patterns often show up after a week or two.
Use the “Behaviour detective log” worksheet to track what happened before, during and after a hard moment.
Common changes and calm responses
Repeated questions, suspicion, agitation, wandering and more. Tap a card.
These changes are common. They are not anyone’s fault. Each card gives a few calm responses to try. What works one day may not work the next, and that is okay.
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The person may not remember they just asked. Repeating can also be a way of expressing worry, boredom or insecurity.
Try this
- Answer calmly, even for the tenth time
- Respond to the feeling: “You’re worried about the bus. I’ll make sure you get there.”
- If they can still read, write the answer on a note or whiteboard
- Offer an activity if they seem bored
- Turn repeated actions into a task, like giving a cloth to help dust
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If the person forgets where they put something, the only explanation that makes sense may be that someone took it. If they forget who you are, you may seem like a stranger. This is called paranoia and is often linked to memory loss.
Try this
- Try not to take it personally or argue about what is true
- Reassure: “Let’s look for it together.”
- Keep spares of things that often go missing, like keys, glasses or a wallet
- Learn their usual hiding spots
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Try this
- Speak calmly and slowly, and listen to their concern
- Reassure them they are safe and you are there to help
- Lower noise and clutter, and let in daylight
- Offer a snack, a drink, music, a walk or folding laundry together
- Take deep breaths and count to 10 if you feel your own temper rising
Lock away car keys, knives, guns and anything that could cause harm. If the person becomes aggressive, step back to a safe distance until it passes.
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Many people become more restless or confused in the late afternoon and evening. Being overtired makes it worse. See “Sleep, nights and sundowning” below for a fuller plan.
Extra things to try
- Stick to the same daily schedule
- Get outside or sit by a window for daylight each day
- Aim for some activity daily, without packing the day too full
- Skip caffeine and alcohol late in the day
- Discourage long naps and late-day dozing
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Pacing or trying to leave may come from boredom, needing the bathroom, trying to “go to work”, or feeling lost even at home.
Try this
- Plan activities and exercise for the time of day they tend to get restless
- Make sure toileting, food and drinks are taken care of
- Create a safe indoor or outdoor area where they can walk freely
The Daily care & safety at home guide has a full wandering plan, including what to do if they go missing.
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The person may be looking for something they can’t name, or they may be hungry or bored.
Try this
- Give them a drawer, box or basket of safe things to sort through
- Lock up dangerous products and remove spoiled food
- Put away important papers, cards, jewellery and keys
- Check bins before emptying them, in case something was thrown out by mistake
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Some people see, hear or feel things that aren’t there, or hold firm beliefs that aren’t true. Tell their care team, since an illness can sometimes cause this.
Try this
- Don’t argue about what they see. Comfort them if they are scared
- Move to another room or go outside together
- Turn off violent or upsetting TV. It may seem to be happening in the room
- Check for shadows, reflections or patterns that could be misread
Sleep, nights and sundowning
Why evenings and nights get harder, and what helps. Tap a card.
Sundowning is a group of changes, not a disease. From dusk into the night, a person may become more confused, anxious, agitated or restless, pace, or have trouble sleeping. The exact cause is not known.
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- Dreams that blur with what is real
- Low light and shadows that are easy to misread
- Mental and physical tiredness after a busy day
- Needing less sleep, which is common with age
- New or confusing surroundings
- Picking up on stress or frustration in people nearby
- A body clock that has them sleepy by day and awake at night
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- Keep regular times for waking, meals and bed
- Get daylight each day, outside or by a window
- Plan outings, appointments and bathing for the morning or early afternoon
- Fit in some activity or a walk, without overloading the day
- Keep naps short if night sleep is poor
- Make lunch the biggest meal, and keep dinner lighter
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- Turn lights on early so the home stays bright as daylight fades
- Lower evening noise: loud TV, chores, busy visitors
- Offer soothing things: calm music, photos, a favourite film
- Skip caffeine, alcohol and nicotine later in the day
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- Approach calmly and speak softly
- Check whether they need something: the bathroom, a drink, to be warmer
- Gently remind them of the time
- Don’t argue. Offer reassurance instead
- Never use physical restraint. Let them pace safely if they need to
Night lights, a room monitor and door chimes help you rest a little easier. The Daily care & safety at home guide has more on night-time safety.
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A bladder infection, incontinence, restless legs or sleep apnea can cause or worsen sleep problems. Tell the care team about sleep trouble, especially if it is new.
Experts generally suggest trying non-drug approaches first. Talk with the clinical provider about any treatment options.
Low mood, worry and losing interest
Depression and anxiety are common in dementia, and support helps. Tap a card.
Depression is very common in people living with Alzheimer’s, especially in the early and middle stages. It can be hard to spot, because dementia and depression share signs like losing interest, pulling away and trouble concentrating.
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In dementia, depression may be milder, may come and go, and may show up as aches, tiredness, irritability or pulling away rather than talk about feeling sad. Later on, the person may not be able to put sadness into words at all.
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Anxiety and agitation can be triggered by a move, travel, a hospital stay, houseguests, a new caregiver, or simply the effort of making sense of things.
What can help
- Listen to the worry and look for its cause
- Offer a comfort object, rest or privacy
- Reassure with calm, simple words
- Lower noise, glare and background TV
- Give energy an outlet: a walk, gardening or dancing to music
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- Keep a predictable routine, with harder tasks at their best time of day
- Plan more of the activities, people and places they enjoy
- Get regular exercise, especially in the morning
- Celebrate small successes
- Find ways for them to help and contribute to family life
- Reassure them they are loved, respected and won’t be left alone
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Support groups for people in the early stage, or one-to-one counselling, can help a person who knows about their diagnosis. Ask the care team about options.
Changes in affection and intimacy
Closeness can change shape. These feelings are common and okay to talk about.
Dementia can change a person’s needs and wishes around closeness and intimacy, and a partner’s feelings may change too. Many couples still find comfort and closeness, even if the way they show it shifts.
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You may want more closeness, or less, than your partner does now. Different levels of interest are common in long relationships, and dementia can make the gap wider.
Ways to stay close
- Holding hands, hugs and sitting close
- Gentle hand or shoulder massage
- Shared music, walks and small couple rituals
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Some types of dementia, especially frontotemporal dementia, can lower inhibitions, so a person may say or do things they never would have before. This comes from the illness.
Calm responses
- Stay calm and don’t shame them
- Gently redirect to another activity or a private space
- Look for unmet needs, like boredom, loneliness or needing the bathroom
- Tell the care team, so they can look for causes and help
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Talking to a trusted friend, a carers’ support group or the care team can help, even if it feels awkward. You are far from the only person facing this.
When and where to get help
When to call the doctor, 911 or a helpline.
Call the care team soon if
- A behaviour is new, sudden or getting worse
- Aggression is new or getting worse
- They are seeing or hearing things that aren’t there
- Sleep, eating or mood change a lot
- You notice possible pain, a fever or signs of infection
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Free and confidential, day or night, with help in more than 200 languages. Staff can help with behaviour changes, communication and safety, and offer free care consultations. Callers who are deaf or hard of hearing can use 711 relay.
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Caregiver support groups, in person or online, and the Alzheimer’s Association’s free ALZConnected online community let you swap ideas with people who understand.
📝 Worksheets for this guide
Fill these in privately in the app. Your answers stay on your phone.
Sources
- Alzheimer’s Association. Depression
- Alzheimer’s Association. Wandering
- Alzheimer’s Association (2026). Alzheimer’s Disease Facts and Figures
- National Institute on Aging (NIA). Communicating With Someone Who Has Alzheimer’s Disease
- Alzheimer’s Association. Communication and Alzheimer’s
- Alzheimer’s Association. Repetition
- National Institute on Aging (NIA) (2024). Alzheimer’s Caregiving: Managing Personality and Behavior Changes
- Alzheimer’s Society (UK). Difficult questions and telling the truth to a person with dementia
- National Institute on Aging (NIA). Coping With Agitation, Aggression, and Sundowning in Alzheimer’s Disease
- National Institute on Aging (NIA). Alzheimer’s Caregiving: Coping With Hallucinations, Delusions, and Paranoia
- Alzheimer’s Association. Suspicions and Delusions
- National Institute on Aging (NIA). Coping With Alzheimer’s Behaviors: Rummaging and Hiding Things
- National Institute on Aging (NIA). Alzheimer’s Caregiving: Home Safety Tips
- Alzheimer’s Association. Sleep Issues and Sundowning
- Alzheimer’s Association. Anxiety and Agitation
- Alzheimer’s Association. Support Groups
- Alzheimer’s Society (UK). How does dementia affect sex and intimacy?
- Family Caregiver Alliance (2008). Caregiving and Ambiguous Loss (by Pauline Boss)
- Alzheimer’s Association. 24/7 Helpline
This guide is for education and self-care. It is not a diagnosis or a substitute for professional care. Please talk to a counselor or clinical provider about your health. Reviewed October 2026.

