Managing Children With Diabetes When They Get Sick

Managing Children With Diabetes When They Get Sick

Children and teens with diabetes do not usually become unwell any more often than children without diabetes. They just need extra care and attention from an adult who has received training from a specialist diabetes team. 


How can an illness affect my child with diabetes?

  • the stress hormones produced during illness can cause changes to blood glucose levels
  • levels can go high or low depending on the type of illness
  • infections that cause fever and pain often cause high glucose levels
  • some medicines, such as oral steroids, can cause high glucose levels
  • vomiting and diarrhoea can cause low glucose levels
  • vomiting can also be a sign of not enough insulin

Key steps to take when managing a child with diabetes when they get sick

Always give insulin

Always give insulin but contact your diabetes team for advice on changing the usual dose if you are not sure.

Go to your family doctor for any illness

Take your child to your family doctor for checking and for any treatment necessary if your child has an illness.

Check and record glucose and blood ketone levels every 2 hours

Check and record glucose levels every 2 hours. If using a flash glucose monitor, check glucose using a finger prick blood test if levels are less than 4 or more than 15mmol/L.

Check blood ketone levels every 2 hours.

Give extra insulin to bring your child's glucose levels down to the target level

Follow the advice you received from your diabetes team on how to correct glucose levels depending on your child's age and insulin needs.

Check the section below 'How and when do I check for ketones in my child with diabetes?'

Encourage eating and drinking fluids

Encourage your child to drink plenty of fluids.

If your child is unable to eat and:

  • if glucose is 10 mmol/l or higher, give water or unsweetened fluids
  • if blood glucose levels are less than 10 mmol/l, offer sweetened fluids such as diluted juice, normal soft drinks, ice blocks or jelly

If your child has been vomiting or has diarrhoea, your diabetes team or doctor may recommend fluids with electrolytes (such as Electral® oral rehydration sachets or Pedialyte®). You can buy these at the pharmacy.

Mini-dose glucagon can sometimes be useful if your child keeps having hypoglycaemia and won't drink or eat anything more. 

See the KidsHealth page about when to use mini-dose glucagon.

When should I call for advice for my child with diabetes when they are sick?

Call your diabetes team if:

  • usual insulin corrections given 3 hourly are not working to bring your child's glucose levels into the target range
  • ketones are not improving despite insulin corrections
  • your child keeps vomiting or complains of tummy pain
  • your child is very drowsy, confused or breathing heavily
  • your child is taking medicine such as Redipred® or prednisolone (steroids)
  • you are worried about your child for any reason

When calling the diabetes nurse or paediatric doctor they will want to know:

  • your child’s age
  • symptoms of the illness such as vomiting or fever
  • any medicine or treatment your child has had, such as paracetamol
  • your child's glucose and ketone levels
  • whether your child is eating and drinking
  • your child's usual insulin doses

Why are ketones and ketone monitoring important for children with diabetes?

  • ketones in diabetes can indicate that there is too little insulin in the body
  • ketones can also result from your child not eating if they are sick
  • ketones are produced by the liver when the body breaks down fat as an alternative form of energy
  • they can occur during illness even when glucose levels are in target range or even low, especially during vomiting
  • they can also occur if glucose levels in the blood are continuously high because insulin doses are too low or injections are missed
  • ketones are measured by a finger prick blood test
  • without treatment, ketones can make your child very sick with ketoacidosis


Ketones can cause the blood to become acidic. High levels of ketones can cause your child to become very unwell with severe dehydration.

If your child has symptoms of ketoacidosis, take them to the nearest hospital emergency department.

The symptoms include:

  • feeling sick (nausea)
  • vomiting
  • tummy pain
  • heavy breathing or making an extra effort to breathe (laboured breathing)
  • your child's breath smelling 'fruity' or like nail polish remover - ketones can do this
  • confusion or drowsiness
  • being unconscious

If your child has these symptoms, take your child to the nearest hospital emergency department.

How and when do I check for ketones in my child with diabetes?

Children and young people with diabetes needing insulin should have a monitor that measures blood glucose and ketones.

Check for ketones:

  • during illness (every 2 hours)
  • if your child is well but their glucose levels are 15mmol/l or higher 3 hours after a usual correction dose of insulin
  • if your child is on an insulin pump and their blood glucose is 12mmol/L or higher

Give extra insulin to bring your child's glucose levels down to the target level

Your diabetes team will give you advice about how to calculate extra insulin doses using the correction factor or insulin sensitivity factor (ISF). If glucose levels remain high, your child will feel increasingly unwell and may develop ketones.

  • if blood ketones are 0.9mmol/L or less, give a correction dose of insulin using the usual correction factor (ISF)
  • if blood ketones are 1.0mmol/L or above, give a correction dose x 1.5 (50% more than the usual, extra insulin dose)
  • if you are unsure about how to do this, contact your diabetes team or local hospital
  • if the blood ketones are not improving within 2 to 3 hours, contact your diabetes team or local hospital
  • if your child or teen is using an insulin pump and ketones are 1.0mmol/L or above, give the correction dose x 1.5 - give this using a pen device or syringe (not the pump) - after this, change the insulin pump site, line and cartridge

What should my sick day management kit contain?

It is important to have supplies at home to help you manage your child when they become unwell. Check it every 6 months to make sure items are not expired and you have these things available:

  • contact details for your diabetes team
  • rapid-acting insulin (NovoRapid®, Humalog® or Apidra®)
  • insulin syringes or pens
  • blood glucose monitor, strips and finger-pricker
  • blood ketone meter and strips
  • food and fluids for sick days such as Pedialyte™, sweetened drinks, ice blocks, unsweetened fluids, soup, glucagon kit and an extra insulin syringe
  • pain relief (such as paracetamol or ibuprofen)
  • thermometer

If travelling, you may need to take medicine for nausea, vomiting and diarrhoea.

Should my child with diabetes have all their immunisations?

Yes, paediatric diabetes teams in New Zealand recommend that all children and young people with diabetes have all their immunisations. Talk with your family doctor about having immunisation against the flu each year. It's free for children and young people with a long-lasting (chronic) condition such as diabetes. See more information about flu immunisation.

See more KidsHealth content on diabetes

Check out KidsHealth's section on diabetes

Screenshot of KidsHealth website diabetes section


The content on this page has been produced in collaboration with the National Clinical Network Children and Young People's Diabetes Services. 

This page last reviewed 28 February 2022.

Call Healthline on 0800 611 116 any time of the day or night for free health advice when you need it