Managing Diabetes During an Illness

The golden rule is, even though you are ill … NEVER STOP YOUR INSULIN!

When the body is fighting illness it will cause the blood glucose levels to rise. This is due to the body’s defence mechanism for fighting illness and infection causing more glucose to be released into the bloodstream. This happens even if you are eating less than usual. Therefore when ill it is essential to manage your blood glucose levels as well as the illness.


Diabetic ketoacidosis (DKA) is a life threatening short-term complication of Type 1 Diabetes. Symptoms of DKA include excessive thirst, feeling nauseated or vomiting, tiredness and confusion, difficulty breathing, stomach pain, breath smelling of pear drops. If you have high blood glucose levels and signs of DKA seek medical advice immediately or go to the nearest emergency department for treatment.

At your Annual Review, get a copy of the sick day guidelines as they apply to YOUR diabetes,. Discuss with your diabetes team what to do in the event of illness, how to manage high blood glucose levels, when and how to test for ketones, when you should seek emergency assistance and who to contact if you need advice out of hours. Have a list of phone numbers for your diabetes team and out of hours GP in a convenient place.

In an emergency when you do not have your own sick day leaflet, download ‘Sick Day Leaflet – Type 1’ for general information on ketones, when to test, what they mean and how to avoid getting them. This information should be in addition to the individualised advice provided by your diabetes team.

Do not exercise if your blood glucose levels are very high and ketones are present, as with lack of insulin your glucose levels may rise further.
NB seek medical help if in ANY DOUBT or:
• Your glucose level remains high
• You have ketones in your urine or blood
• You are unable to eat
• You are vomiting or unable to keep down fluids
• Your temperature remains high
• Your glucose levels persist below 4mmol/l