Sick Day Rules with Type One Diabetes

The Affect of Illness on Blood Sugars

There are so many day to day factors that affect blood sugars of people with Type One diabetes, from stress, nerves, excitement, the weather, exercise to name a few. One of the unavoidable yet most complex ones to manage is sickness. Depending on the type of illness they can either elevate sugars or cause them to plummet.

I am Rachel, a mum of two girls, one of which is 7 years old and has been Type One for 3 and a half years now. Having a child at primary school, we pick up all sorts of bugs and germs and I want to share some of the sick day tips I have picked up along the way. I’ve also included a link to some really helpful sick day guidelines from the University College Hospital, London which give a great reference point.

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Illnesses that Elevate Blood Sugars

Generally speaking most illnesses elevate blood glucose as the body’s way of combating the illness or infection is to release additional glucose into the blood stream. These illness could include a common cold, the flu, infections of any sort. High blood glucose levels can lead to dehydration so its important to drink plenty, this can also help to flush through any infection.

Illnesses that Lower Blood Sugars

Vomiting and diarrhoea are the illnesses that tend to cause blood glucose levels to plummet. They can be extremely difficult to manage and in severe cases can require hospitalisation in order to maintain safe control by administering glucose intravenously.

It is sometimes difficult to tell initially if elevated blood readings are due to illness or a change in dosing required or sometimes a pump or cannula fail. If blood glucose levels are elevated for an extended period of time they should be monitored closely. All the relevant checks should be made on the pump i.e. cannula, insulin and line changed and a correction given via pen. If they still remain elevated it important to check for ketones as they can be an early sign of Diabetic Ketoacidosis (DKA) and an indication that additional insulin is required.

What is DKA?

Diabetic ketoacidosis (DKA) is a condition that happens when blood glucose levels are consistently high. It happens when a severe lack of insulin means the body cannot use glucose for energy, and the body starts to break down other body tissue as an alternative energy source. Ketones are the by-product of this process and are are poisonous chemicals which build up and, if left unchecked, will cause the body to become acidic – hence the name ‘acidosis’.

DKA is a life-threatening emergency and medical help should be sought immediately as it can be easily treated with insulin, extra glucose and fluid if caught early but fatal if left too late.

Signs of DKA

It is important to be aware of the signs of DKA so you can recognise them and seek medical advice if necessary. They are basically they symptoms that anyone could have upon diagnosis with Type One diabetes and include: thirst, excessive urination, tiredness, blurry vision, the smell of pear drops on breath, abdominal pain and nausea are the main ones.

Dealing with Sickness

1. Test bloods regularly

It is recommended to test bloods every 2 hours when sick or monitor closely if on a CGM to prevent dangerous highs and lows.

2. Test ketones frequently .

Ideally ketones should be monitored and tested every 4 hours to prevent DKA and adjust insulin doses accordingly.

3. Always take insulin.

Whilst it is probably recommended to reduce your basal/ background insulin perhaps by around 25%, it is still important to always continue taking insulin even if you are not eating as this helps to keep ketones at bay. If you are unable to keep food down, you must take drinks with carbohydrates in instead such as full fat coke, milk, fruit juice or dioralyte solution.

4. Stay Hydrated .

It is essential when you are sick with Type One to replace the fluids that are lost. If unable to keep fluids down try a re-hydration drink such as dioralyte as these are balanced to re-hydrate and replace fluid and body salts lost through sickness and diarrhoea. They also have a carbohydrate value so can be used to keep blood glucose up.

A rough guideline is to mix up a sachet with 200ml water, which equates to 10g of carb. Deliver insulin for the 10g then take tiny sips every 15 mins over the next 4 hours (time the insulin is active for).

5. When to seek medical help.

If you are unable to keep any food down and blood glucose levels continue to plummet and especially if ketone levels are rising, it is essential to seek medical advice immediately as assistance may be required to help stabilise your levels with glucose and insulin and this sometimes needs doing intravenously.

Here are two really useful resources for monitoring blood and ketone levels throughout sickness:


SICK DAY RULES for Insulin Pump Users

Real Life Mum of a Type One Tips

So there you have the basics and two really helpful resources for both managing sickness on the pump and MDI. Having had a fair few sickness bugs since diagnosis and ending up in hospital with out first one (only two weeks after diagnosis) it has always been my aim to be on the case as soon as the bug strikes to do all that I can to avoid my daughter being hospitalised, because lets face it, who wants to be in hospital when your ill with a sickness bug? That would be no-one!

I wanted to share just a few tips I’ve picked up that haven’t been mentioned already that may help you out.

  • Some bugs are mild – not every sickness bug is difficult to manage, some are fairly mild with only vomiting a few times fairly spread out and hardly need any adjustments to basal insulin so don’t be too hasty to make changes, just monitor closely to start with.
  • For me ketones are the deciding factor, if they are on the increase its a sign that things are out of balance so I check them straight away after the first bout of sickness and then 4 hourly after that.
  • If we are hovering a bit low I will start by reducing the basal insulin by 10-20%.
  • If it is a violent bug and vomiting is frequent and my daughter is unable to keep anything down, I tend to use glucojuice as my go to sugary drink as she doesn’t like anything fizzy and its more concentrated than a fruit juice so doesn’t need to drink as much of it. I have heard other people recommend flat full fat coke but its down to personal preference.
  • If we are struggling to keep anything down, I have discovered if she drinks 4/5 sips of glucojuice straight after being sick, it gives it maximum chance of absorption before being sick again so it does work at elevating sugars slightly. This followed by 1 or 2 sips every 15/20 minutes, little and often is the key for keeping as much down as possible.
  • Sugary ice-lollies can sometimes be stomached when other food can’t be.
  • My daughter hates the taste of dioralyte so won’t drink it but if she is really sick, she knows it and will agree to taking tiny sips when shes at her worst which as mentioned above allows me to bolus for 10g and she has tiny sips over a few hours to raise her sugars but also keep her hydrated.
  • I refer to the UCLH Sick Day Rules Guidelines given above to keep a check on ketone levels and when to correct and seek additional support.
  • If we are struggling I also check in with my DSN on the phone who is also sometimes able to give helpful advice if we need it.
  • Coffee, drink lots of coffee to stay awake. There’s no doubt about it managing sickness of a Type One child over night is a tiring business.
  • Remember if you think things are out of

Finally here is a fantastic little summary of illness with Type One from Diabetes UK.

I hope you have found this article helpful. If you would like to see more of my posts and join my little Type One community please sign up on my homepage. It would be great to have you join us!

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