Dehydration – what’s the deal?

What is dehydration? to put it simply, it’s a lack of hydration. Dehydration happens when the body doesn’t have enough fluid to function properly.

Unfortunately children can dehydrate easily when they are sick, this is because they have less fluid volume and less fluid reserves compared to adults.

What causes dehydration?

Lots of things actually!

The main culprits are gastro, diarrhoea, vomiting, fevers, warm weather, increased physical activity, refusal to drink; and illnesses that make it uncomfortable for kids to eat and drink such as tonsillitis or hand, foot and mouth disease.

Realistically, every time your child is sick, you should be thinking about hydration and dehydration.

So what signs or symptoms should I be looking out for?

Mild-moderate dehydration

  • Fewer wet nappies than normal and / or less heavy than usual (older kids may go to the toilet less)
  • Dark or strong smelling urine (urine should be pale yellow)
  • Dry lips, tongue or mouth

Severe dehydration

  • Extremely thirsty
  • Pale or mottled skin
  • Drowsy, floppy or unresponsive
  • Sunken fontanelle (soft spot on a baby’s head)
  • Sunken eyes
  • Fewer or no tears when crying
  • Breathing faster than normal

If your child has any signs or symptoms of severe dehydration phone 000 for an ambulance or get them to an emergency department urgently.

Okay, so I think my child has mild / moderate dehydration, what should I do?

Make a GP appointment or take your little one down to an urgent care centre ASAP.


Under six months

  1. Continue to offer breastmilk or formula but do so more frequently (there is no need to give water as breast milk and formula have all the good stuff young babies need).
  2. After your appointment your doctor might advise you to give an oral rehydration solution (Hydralyte/Gastrolyte etc).
  3. Monitor closely for signs of severe dehydration.

Over six months

  1. Depending on your child’s age continue to offer breast milk, formula or water, but more frequently
  2. For babies under 12 months you should prioritise breast milk or formula feeds unless your GP advises otherwise.
  3. You can also give oral rehydration solutions (Hydralyte/Gastrolyte) a go and have a chat with your friendly pharmacist for advice.
  4. Off their solids? Try not to worry too much as this is totally normal. Sometimes pain relief can help encourage kids to eat if it’s discomfort keeping them from eating. Alternatively apple juice diluted (1 part juice, 4 parts water) is a great way to keep fluids and blood sugar up. Try to avoid sports drinks or soft drinks as too much sugar can actually worsen dehydration.
  5. If your child is old enough and they are not so keen on an oral rehydration solution, pick up some Hydralyte icy poles from the chemist, these are a serious game changer.
  6. Monitor closely for signs of severe dehydration.

Hot Tip: If your child is struggling to keep down fluids it can help to offer small amounts of fluids more frequently. This is because sometimes when kids are sick, large amount of liquid can upset the stomach and cause vomiting (eg: Gastro).

Alright team, quick recap

Kids dehydrate quickly. When they are sick, exercising or out in the warm weather, it’s important to focus on hydration and look out for signs of dehydration.

If your child has signs of mild or moderate dehydration you should see a doctor as soon as you can, particularly if they are under six months. Continue to encourage fluids, consider oral rehydration solutions if age appropriate and if your child has any signs of severe dehydration you should call 000 for an ambulance or get them to the emergency department urgently.


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