Dehydration means your body loses more fluids than you take in. If it's not treated, it can get worse and become a serious problem.
Babies, children and the elderly are more at risk of dehydration.
Check if you're dehydrated
Symptoms of dehydration in adults and children include:
- feeling thirsty
- dark yellow and strong-smelling pee
- feeling dizzy or lightheaded
- feeling tired
- a dry mouth, lips and eyes
- peeing little, and fewer than 4 times a day
Dehydration can happen more easily if you have:
- vomiting or diarrhoea
- been in the sun too long (heatstroke)
- drunk too much alcohol
- sweated too much after exercising
- a high temperature of 38C or more
- been taking medicines that make you pee more (diuretics)
How you can reduce the risk of dehydration
Drink fluids when you feel any dehydration symptoms.
If you find it hard to drink because you feel sick or have been sick, start with small sips and then gradually drink more.
You can use a spoon to make it easier for your child to swallow the fluids.
You should drink enough during the day so your pee is a pale clear colour.
Drink when there's a higher risk of dehydrating. For example, if you're vomiting, sweating or you have diarrhoea.
Carers: making sure someone drinks enough
Sometimes people you care for do not have a sense of how much they're drinking.
To help them:
- make sure they drink during mealtimes
- make drinking a social thing, like "having a cup of tea"
- offer them food with a high water content – for example, soups, ice cream or jellies, or fruits like melon
A pharmacist can help with dehydration
If you're being sick or have diarrhoea and are losing too much fluid, you need to put back the sugar, salts and minerals that your body has lost.
Your pharmacist can recommend oral rehydration sachets. These are powders that you mix with water and then drink.
Ask your pharmacist which ones are right for you or your child.
Non-urgent advice: See a GP if:
- your symptoms do not improve with treatment
Immediate action required: Call 999 or go to A&E if:
- you're feeling unusually tired
- you're confused and disorientated
- any dizziness when you stand up does not go away
- you have not peed all day
- your pulse is weak or rapid
- you have fits (seizures)
These can be signs of serious dehydration that need urgent treatment.
Under-5s with dehydration
The under-5s should get plenty of fluids to avoid dehydration.
It's quite common for young children to become dehydrated. It can be serious if it's not dealt with quickly.
Urgent advice: Take your baby or child to the GP urgently or go to A&E if they:
- seem drowsy
- breathe fast
- have few or no tears when they cry
- have a soft spot on their head that sinks inwards (sunken fontanelle)
- have a dry mouth
- have dark yellow pee or have not had a pee in last 12 hours
- have cold and blotchy-looking hands and feet
Once the dehydration has been treated, your child will need to maintain their fluid levels.
GPs usually advise:
carry on breastfeeding or using formula – try to give small amounts more often than usual
for babies on formula or solid foods – give them small sips of extra water
give small children their usual diet
give regular small sips of rehydration solution to replace lost fluids, salts and sugars – ask your pharmacist to recommend one
do not make formula weaker
do not give young children fruit juice or fizzy drinks – it makes things like diarrhoea or vomiting worse
Page last reviewed: 9 August 2019
Next review due: 9 August 2022