The short answer
- It can move from mild to an emergency within a dayThe signs form three stages, and knowing which one you are looking at decides what to do next.
- Older people lose the early warning systemA fading sense of thirst and less efficient kidneys mean dehydration can set in before anyone feels thirsty.
- It is linked to real, measured harmIn a UK hospital study, older patients who were dehydrated on arrival were far more likely to die within 30 days than those who were not.
- Know which signs mean 111 and which mean 999The two lists are different, and it helps to have the actual signs rather than a general sense of concern.
The NHS names older adults as one of the groups more at risk of dehydration, and Age UK lists it as one of the most common reasons an older person is admitted to hospital.
The short answer
Yes, and it can move from mild to an emergency within a day
Most dehydration in later life is mild and put right with a drink and a bit of watching. It is worth taking seriously because of how fast it can change, and how easily the early signs in an older person get put down to something else. The three stages below use the same signs NHS guidance gives for dehydration in adults, grouped by what to do at each one.
Early signs
Offer fluids nowWhat it can look like: Thirst, a dry mouth, a headache, feeling tired, and urine that is darker than usual.
This is the stage most people picture, and in an older person it is the one most easily missed, because the sense of thirst that would normally give the warning is often the first thing to fade with age.
Getting worse
Call 111 todayWhat it can look like: Dizziness on standing that does not settle, a faster heart rate or breathing than normal, and passing noticeably less urine than usual.
Ask for an urgent GP appointment or call NHS 111. These are the exact signs NHS guidance treats as needing same-day advice rather than a wait-and-see approach.
Emergency
Call 999What it can look like: Pale, grey, blue or blotchy skin or lips, skin that feels cold, difficulty breathing, confusion, or being unusually sleepy and hard to wake.
Call 999 or go to A&E. In a study of older people admitted to a UK hospital as an emergency, those who were dehydrated on arrival were far more likely to die within 30 days than those who were not, so this stage is never one to wait out at home.
The NHS names babies, young children and older adults as the groups most at risk of dehydration, and it is one of the most common reasons an older person ends up in hospital, according to Age UK. That is not because it is unusual. It is because it can move quickly, and because the early stage is easy to mistake for tiredness, a headache, or simply having an off day, rather than fluids. What are the symptoms of dehydration in the elderly? has the fuller list to check against if you are not sure which stage above fits. This sits inside the wider picture of elderly care, where fluids are one of several everyday things worth keeping an eye on.
Why it happens
Why an older body loses its own early warning system
The reasons dehydration catches older people out are physical, not a matter of forgetting to drink. Several ordinary changes of later life work against a full glass of water, often at the same time.
The sense of thirst fades
The kidneys hold on to less water
Some medicines increase fluid loss
Getting to a drink is not always straightforward
None of this makes dehydration inevitable, and each of these has a fix. Why might an older person be reluctant to drink fluids? looks at the reasons behind a specific refusal, and how can I get my elderly relative to drink more fluids? has practical ways round each one. If a new medicine has changed how much your relative is drinking or how often they need the toilet, that is worth mentioning to the GP or pharmacist rather than working around it alone.
What it leads to
The health problems dehydration causes or makes worse in later life
Being told dehydration is serious does not mean much on its own. These are the specific problems it is linked to when it is not caught early, and the figures behind why hospitals treat it as more than a minor issue in older patients.
37%
of older patients were dehydrated when admitted to hospital as an emergency
Nottingham University Hospitals NHS Trust, 2015
16%
died within 30 days if dehydrated on admission
compared with 4% of those who were not
Age and Ageing, 2015 (the HOOP study): 200 emergency admissions aged 65 and over at a single UK teaching hospital.
Age UK links dehydration in older people to a higher risk of urinary tract infections, falls and pressure ulcers, and notes that the signs are often mistaken for other age-related conditions, including dementia, which is part of why it goes unrecognised. NICE guidance on delirium, the sudden confusion that is common in hospital, names dehydration as one of the factors that can bring it on or make it worse, alongside things like infection, constipation and pain.
Getting help quickly
Knowing which signs mean call 111 and which mean call 999
The three stages above give the shape of it. Here is exactly what NHS guidance says to do at each one, because in the moment it helps to have the actual signs rather than a general sense of concern.
What to do, by sign
0 of 9 ticked
Ask for an urgent GP appointment, or call NHS 111
Call 999, or go to A&E
None of this needs a diagnosis first. If you are unsure which list fits, treat it as the more serious of the two and call accordingly. A paramedic or GP would always rather be called and find it was not needed than the other way round. What to do if an elderly person is dehydrated covers what happens next, and what is the fastest way to hydrate an elderly person? covers the practical side once help is on the way.
Lowering the risk
What raises the risk further, and what helps most days
Most dehydration in older people is prevented with an ordinary routine of drinks through the day. It helps to know the situations that turn everyday risk into something worth watching more closely.
Extra care in these situations
- Extra fluids in hot weather, since older people are less efficient at recognising and responding to heat
- A drink offered on a routine, with meals and tablets, rather than waiting to be asked
- A quick word with the GP or pharmacist after any new water tablet or laxative is started
- Extra fluids during a stomach bug, a fever, or anything that causes sweating, vomiting or diarrhoea
- A bit more watchfulness for the first few days after moving into a care home or coming home from hospital, when routines change
What tends to make it worse
- Cutting back on fluids because of worry about reaching the toilet in time, which usually makes the underlying problem worse
- Waiting for thirst as the signal to offer a drink
- Assuming hot weather is only a risk for the very old or the already unwell
- Leaving a change in drinking or urination unmentioned at the next GP visit if it started after a new medicine
The target to aim for is at least 1,600ml (about 3 pints) a day for women and 2,000ml (about 3½ pints) for men, according to the British Dietetic Association's guidance for older adults, from ordinary drinks and water-rich food together. Does tea count as water intake? is worth reading if you are wondering whether tea and coffee count towards that (they do).
A regular carer's visit is also one of the more effective ways to catch a drop in drinking before it becomes serious, because the same person sees what is normal for your relative and notices sooner when a cup has gone untouched. Companion carers on PrimeCarers charge £15 to £20 an hour with our fee included, and a lunchtime or afternoon visit fits this kind of routine well. How much does a companion carer cost? has the detail.
Questions
Questions families ask about how serious dehydration is
It can be, though most dehydration is mild and put right with fluids. It becomes an emergency when it comes with pale, grey, blue or blotchy skin, cold skin, difficulty breathing, confusion, or being unusually sleepy and hard to wake. Any of those means calling 999 or going to A&E rather than waiting to see if it passes.
Severe dehydration can, particularly once it leads to a serious drop in blood pressure, kidney injury or a fall. In a UK hospital study, older patients who were dehydrated on admission were far more likely to die within 30 days than those who were not, 16% against 4%, which is one reason hospitals treat it as more than a minor issue in older patients. The study, in Age and Ageing, has the full figures.
Faster than a younger adult, sometimes within a day, because the usual early warning, feeling thirsty, is often the first thing to fade with age. A hot day, a stomach bug or a new water tablet can move things along quickly, which is why a routine of offered drinks matters more than waiting to be asked.
Dizziness on standing that does not settle, a faster heart rate or breathing than usual, dark urine or passing much less than normal, and unusual tiredness. Any of these means asking for an urgent GP appointment or calling NHS 111 the same day. What are the symptoms of dehydration in the elderly? has the fuller list.
Yes, to both. NICE guidance on delirium names dehydration as one of the factors that can trigger sudden confusion in older people, and Age UK links dehydration to a higher risk of falls, urinary tract infections and pressure ulcers. Confusion is sometimes the first thing a family notices, before anyone has thought about fluids.
At least 1,600ml (about 3 pints) a day for women and 2,000ml (about 3½ pints) for men, according to the British Dietetic Association's guidance for older adults, from ordinary drinks and water-rich food together. How can I get my elderly relative to drink more fluids? has practical ways to reach it.
Yes. A carer who visits at the same times each day gets to know what is normal for your relative and notices sooner when a drink has gone untouched. Companion carers on PrimeCarers charge £15 to £20 an hour with our fee included. How much does a companion carer cost? has the detail.