Dehydration in Older People: symptoms, self-care and when to get help
Checked against current published health guidance — last reviewed 2026-09-23. See how we check.
Older people can become dehydrated more easily because the sense of thirst weakens with age. Signs include dark, strong-smelling urine, peeing less often, dizziness, tiredness and confusion. Offer drinks regularly, and get urgent help if someone is very confused, drowsy or has not peed all day.
Overview
Dehydration happens when the body loses more fluid than it takes in. In older people it is often linked to a reduced sense of thirst, illness such as diarrhoea, vomiting or a high temperature, hot weather, some medicines, or worry about needing the toilet.
Even mild dehydration can cause headaches, tiredness and constipation, and it can make confusion, falls and urine infections more likely.
What may help
- Offer drinks regularly through the day rather than waiting for thirst
- Keep a drink within easy reach and use a cup that is easy to hold
- Include foods with a high water content, such as soups, fruit, jelly and yoghurt
- Water, milk, tea and coffee all count towards fluid intake
- Drink more in hot weather or during illness
When to see a pharmacist or GP
- Signs of dehydration that do not improve after drinking more fluids
- Dehydration linked to diarrhoea or vomiting that is not settling
- Concerns that a medicine may be causing fluid loss
When it could be an emergency
- New or worsening confusion, or being very drowsy or hard to wake
- Not peeing all day
- A fast heartbeat, fainting or a fit (seizure)
- Feeling very unwell with vomiting that means they cannot keep fluids down
If any of these apply, don't wait — call your local emergency number (see emergency numbers by country, or Red Flags in the app), or go straight to your nearest emergency department.
Want more detail, tailored to your own situation?
Look up "Dehydration in Older People" in the appCommon questions
What are the signs of dehydration in older people?
Feeling thirsty, dark yellow strong-smelling urine, peeing less often, dizziness, tiredness, a dry mouth, headaches and, in more serious cases, confusion.
How much should an older person drink?
A common guide is 6 to 8 drinks a day, and more in hot weather or during illness. A GP can advise if someone has heart or kidney problems that affect how much they should drink.
Can dehydration cause confusion?
Yes. Dehydration is a common cause of sudden confusion in older people, and it needs prompt attention.
Do tea and coffee count?
Yes. Tea and coffee count towards daily fluid intake, as do milk, water and drinks such as squash.
Official sources
Related topics
Sudden Confusion (Delirium)
Sudden changes in thinking need urgent attention.
Falls in Older People
What to do after a fall, and how to prevent the next one.
Urinary Tract Infection (UTI)
Symptoms, self-care, and when it's serious.
Heat Exhaustion and Heatstroke
Cool down fast, and know when it is an emergency.
General information only, last checked 2026-09-23 — not medical advice and not a diagnosis. This page doesn't cover every cause or every person's situation; for anything specific to you or someone in your care, speak to a pharmacist, GP, or other qualified professional. See how we check. Be Health Wise is part of the Be Wise family of apps.