Communication and Behaviour Changes in Dementia: A Practical Guide

Nobody quite warns you about this part. Raising early concerns about a parent is one thing, but once dementia has progressed, the day-to-day skill of actually talking to them, and making sense of behaviour that seems to come from nowhere, is a completely different challenge. This isn't medical advice, and it won't cover medication. It's the practical, moment-to-moment part: how to communicate, what's usually behind agitation and repeated questions, and what sundowning actually is.

Why behaviour changes happen

Agitation, repeated questions, and resistance to help usually aren't defiance. They're often the only way someone can express something they can no longer put into words, discomfort, confusion, fear, or an unmet need like hunger, thirst, or needing the toilet.

Worth knowing: a sudden or marked change in behaviour, particularly if it happens over hours or days rather than gradually, can be a sign of an infection (urinary tract infections are a very common cause, often linked to not drinking enough), pain, or a reaction to medication, not the dementia itself progressing. It's worth a same-day conversation with the GP rather than assuming it's "just the dementia" and trying to manage it alone.

Communication techniques that actually help

• Don't argue with their reality. If they say something that isn't true, correcting it rarely helps and often increases distress. Responding to the feeling behind it, "that sounds worrying," "I can see that's upsetting", usually works better than correcting the facts.
• Watch your own tone and body language as much as your words. Calm, unhurried, and warm carries more than what's actually said.
• Explain before you act. Say what you're about to do before you do it, especially for personal care or anything involving touch, so it doesn't feel sudden or done to them rather than with them.
• Redirect rather than confront. A different activity, a familiar object, or a change of subject often defuses a moment that arguing would only escalate.
• Offer reassurance generously. Confusion is frightening. Hearing "you're safe, I'm here" is rarely too much, even if it needs repeating.

Understanding sundowning

Sundowning is a pattern of increased confusion, agitation or restlessness that tends to appear in the late afternoon or evening. It's extremely common in dementia, and it isn't a separate illness, it's a recognised pattern linked to the condition itself. It can be one of the most exhausting parts of caring, disrupting evenings and sleep on both sides.

There's no single cause, but common contributors include tiredness building up through the day, a disrupted internal body clock, and low evening light creating shadows and confusion. Physical discomfort, hunger, or needing the toilet can also show up as sundowning-style agitation.

Things that often help:

• A consistent daily routine, so the day feels predictable rather than uncertain
• Daylight exposure earlier in the day, even just sitting near a window
• Reducing caffeine later in the day
• A calm, unhurried evening routine, with lighting adjusted gradually rather than switching from bright to dark suddenly
• Familiar objects, photos, or music in the evening, rather than introducing anything new

Medication is not usually the first approach to sundowning, and should only be considered after a proper medical review, non-drug approaches are recommended first.

Sundowning is about evening agitation specifically. If it's night-time waking or day-night confusion you're dealing with instead, that's covered in more depth in our dedicated sleep disturbance guide →

When to get medical input rather than manage it alone

Contact the GP the same day if a behaviour change is sudden, severe, or comes with any physical symptoms. It's easy to assume every change is "just the dementia," but treatable causes like infections and pain are common and worth ruling out first.

A hospital stay is one specific trigger worth knowing about in advance: confusion often gets noticeably worse afterwards, a recognised, common pattern rather than a sign of sudden decline. If someone's just been discharged and seems different, read what actually happens during a hospital admission, and why.

For ongoing, difficult, or escalating behaviour that's genuinely hard to manage, Dementia UK's Admiral Nurses offer free, specialist, dementia-specific advice by phone. Worth calling for support with a difficult pattern, not just as a last resort when things feel unmanageable.

If shouting, swearing, or verbal aggression specifically is what you're dealing with, that's covered in more depth, including a real safety incident and how to travel by car safely, in our dedicated guide on aggression in dementia →

A word from The Care Compass

If you've found yourself exhausted by an evening that seemed to come out of nowhere, or unsure whether to correct something that wasn't true, you're not doing this wrong. This is genuinely one of the hardest, least-talked-about parts of caring, and it gets easier with the right information, not with trying harder alone.

This article is for general guidance only and does not constitute medical advice. For anything involving a sudden change, pain, or a decision about medication, speak to a GP or specialist directly.

You don’t have to navigate it alone.