• Even though you may not be eating during an illness such as a cold, fever, diarrhea or vomiting, there is plenty of sugar entering your blood from the stores inside your body. 
    • However, vomiting or not eating can result in dangerously low blood sugar if you do not eat for long enough time. You must keep checking your blood sugar.
  • Surprisingly, a diabetic may need even more insulin during illness. You must check your blood sugar more frequently and contact your doctor who may advise an extra dose of insulin.
  • When ill, diabetics should drink plenty of non-surgery fluids and check their temperature. Vomiting can quickly result in dehydration, and you may need to go to the hospital for intravenous fluids.
  • Different medicine will affect your blood sugar differently, so make sure to keep checking your blood sugar and check what is in the medicine you are taking. You can ask your doctor if they know how it will affect your sugar, but they may not know for sure.
  • Be careful when mixing different medicines. Always check with your doctor first before doing so.
  • The better your sugars are when you are sick, the faster and better you will recover. It is so important to keep track of your sugars very carefully when you are sick.


Information and images from are from or inspired by Living the Sweet Life with Diabetes: The Art of balancing insulin, diet, and exercise by Dr. Santosh Gupta, MD, MRCP (UK), CDE.  You can access the book here:

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