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child drinking

Here’s how to make sure your child or baby stays protected from dehydration.

What is dehydration?

Dehydration means the body loses more fluids than it takes in. If it isn't treated it can get worse and become a serious problem.

"Babies, children and the elderly are at the highest risk of dehydration (NHS Choices, 2017)."

Dehydration: the causes

Illnesses like diabetes, vomiting, diarrhoea, heatstroke, or a fever increase the risk of dehydration (NHS Choices, 2017). Conditions that make it hard to drink fluids (like a sore throat) can also put children at risk of dehydration (Kids Health, 2017).

Children are also at an increased risk if they:

  • Are younger than one year old, particularly if they are younger than six months old.
  • Had a low birth weight.
  • Have not been offered or have not been able to tolerate extra liquids.
  • Have stopped breastfeeding during the illness.
  • Show signs of malnutrition. (NICE, 2009)

How do I prevent dehydration in babies?

If your baby is at risk of dehydration, carry on breastfeeding or using formula but go with the little and often approach. That is feeding them small amounts more frequently.

Babies that breastfeed don’t need extra water as long as they can feed when they need to. They’ll probably feed more in hot weather.

Babies that are formula fed can have sips of plain, cooled, boiled water in a small cup or bottle on top of their usual formula. They may behave as though they are hungry but if they then reject the feed, it may be that they’re actually thirsty.

How do I prevent dehydration in children?

When they’re at risk of dehydration, give small children their usual diet along with some extra water. Homemade ice-lollies are a great way to stay cool when it’s hot outside.

Breastfeeding in the heat: a comfort issue

You might get hot and sweaty when you’re holding your baby for a feed but don’t feel embarrassed – a lot of us have been there. You could place a piece of muslin between your body and your baby’s to help you both feel more comfortable.

Dehydration symptoms: what to look out for

Some of the symptoms of dehydration in children can be:

  • feeling thirsty
  • dark yellow and strong-smelling wee
  • feeling dizzy or lightheaded
  • feeling tired
  • dry mouth, lips and eyes
  • weeing little and less than four times a day
  • soft spot on their head that sinks inwards
  • cold and blotchy-looking hands and feet
  • few or no tears when they cry
  • sunken eyes. (NHS Choices, 2017)

More severe symptoms like an abnormally fast heartbeat (tachycardia) and/or abnormally rapid breathing (tachypnoea) can be signs of clinical dehydration (NICE, 2009).

Treatment for dehydration

If they are dehydrated but not clinically dehydrated or at an increased risk of dehydration, continue children’s feeds as normal and add extra liquids (NICE, 2009). For extra liquid, stick to water and try to avoid fizzy drinks or fruit juice.  Keep giving your child small sips of liquid and gradually make them drink more if they can. You could use a spoon to make it easier (NHS Choices, 2017).

Children at increased risk of dehydration

If your child is at increased risk of dehydration, do the same as above but also offer them oral rehydration therapy solution (ORS) for extra liquid. You can buy oral rehydration therapy solution from the chemist, where they can recommend one that’s ok for your child (NICE, 2009). If this doesn’t help, see your GP.

Clinically dehydrated

If your child is clinically dehydrated, give them oral rehydration therapy solution and continue to breastfeed. But do not give other oral liquids without advice (NICE, 2009). Make sure you seek advice if they won’t take it or if they vomit. Do not give solid foods.

After your child has rehydrated

When they are rehydrated, keep encouraging them to drink plenty of their usual fluids. Reintroduce food and avoid fizzy drinks and fruit juice once their diarrhoea has stopped.

In children at increased risk of dehydration recurring (see above), consider giving 5 ml/kg of oral rehydration therapy solution after each large watery stool.

This page was last reviewed in March 2018.

Further information

Our support line offers practical and emotional support with feeding your baby and general enquiries for parents, members and volunteers: 0300 330 0700.

You might find attending one of our NCT New Baby courses helpful as they explore different approaches to important parenting issues with a qualified group leader and allow you to meet other new parents in your area.

Make friends with other parents-to-be and new parents in your local area for support and friendship by seeing what NCT activities are happening nearby.

Read more about dehydration from NHS Choices.

Kids Health. (2017) Dehydration. Available from: [Accessed 1st March 2018].

NHS Choices. (2017) About dehydration. Available from: [Accessed 1st March 2018].

NICE. (2009) Diarrhoea and vomiting caused by gastroenteritis in under 5s: diagnosis and management Clinical guidelines. Available from:… [Accessed 1st March 2018].

Further reading

Hartling L, Bellemare S, Wiebe N, Russell K, Klassen TP, Craig W. (2006) Oral versus intravenous rehydration for treating dehydration due to gastroenteritis in
children. Cochrane Database Syst Rev. 19(3):CD004390. Available from: [Accessed 1st March 2018].

Patient. (2014) Dehydration in children. Available from: [Accessed 1st March 2018].





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