As a new parent or guardian, looking after children can be a wonderful experience but it can also bring a lot of worry. There may be a lot of questions running through your mind but the one that is constantly there is about the health of your child. One particular concern you may have is with dehydration. Here are some of the symptoms you should look out for in relation to dehydration in children.

Symptoms of Dehydration1:

  • Nausea/headaches
  • Dizziness
  • Dark yellow or brown urine
  • Less urination than usual
  • Extremely thirsty
  • Less active
  • Pale and sunken eyes
  • Feeling cold

Headaches and Dizziness

For a child’s body to function properly, they need it to contain a healthy balance of fluids and electrolytes2. But as their body becomes dehydrated, they may experience headaches. This occurs because their brain temporarily contracts or shrinks due to the fluids they have lost, causing the brain to pull away from the skull and hence causing pain/headaches2. By rehydrating, the brain can go back to its normal state2.

Dark Yellow Urine or Less Urination

A dark yellow colour, or experiencing less urination, are symptoms from not having enough fluids in your body and hence dehydration occurs3.


One of the indicators of dehydration is being thirsty. However, becoming thirsty is not a warning that dehydration is about to occur. Becoming thirsty is a result from becoming dehydrated4.

Becoming less active

Seeing a child being less active than usual can bring concern to a parent or guardian. Bodies that are low on fluids can make someone feel tired or more weaker than usual5. Restoring lost fluids can then provide energy.

Pale and Sunken Eyes

Pale and sunken eyes are a sign of severe dehydration1. When this occurs, you will need to see your GP or visit your closest hospital’s emergency department as soon as possible1.

Why does dehydration occur?

Dehydration can occur due to multiple factors, including:

  • Heat
  • Diarrhoea or Vomiting
  • Exercise or physical activity
  • Travel
  • Fever

If diarrhoea persists for more than 6 hours in infants under 6 months, 12 hours in children under 3 years, 24 hours in children aged 3-6 years, or 48 hours in children over 6 years, then seek medical advice from your health professional.  

How can I help?

Your child is likely already dehydrated if they are showing any of the symptoms from above. Water may not completely do the job as it’s important to replenish lost electrolytes too.

This is where BIOLyte can come in handy. BIOLyte can aid in fast rehydration and replenish lost electrolytes. Available in sachet, ready to drink and effervescent formats, it’s a convenient solution to have to relieve symptoms of dehydration.


  1. The Royal Children’s Hospital Melbourne 2018, Dehydration, Parkville Victoria, <https://www.rch.org.au/kidsinfo/fact_sheets/Dehydration/>
  2. Fletcher, J. 2017, How to Recognise a Dehydration Headache, Medical News Today, Gloucestershire England, <https://www.medicalnewstoday.com/articles/317511>
  3. Johnson, J. 2019, What to know about low urine output, Gloucestershire England,
  4. Solo-Josephson, P. 2017, Dehydration, <https://kidshealth.org/en/teens/dehydration.html>
  5. Harvard Health Publishing n.d., Fight Fatigue with Fluids, Harvard University, <https://www.health.harvard.edu/healthbeat/fight-fatigue-with-fluids>