Managing Illness and Sick Days
Illness can make blood sugar levels harder to control. Knowing how to adjust medication, stay hydrated, and monitor glucose more often can help you stay safe and recover faster.
This content is not medical advice. Always consult your endocrinologist, doctor or diabetes care team before making any changes to your diabetes treatment or daily management.
How to Manage Diabetes When You’re Sick?
Being sick can make diabetes management more challenging. Even a mild cold or stomach virus can affect your blood glucose levels. Having a clear plan for insulin, hydration, and food can help you stay safe and recover faster.
How Illness Affects Blood Glucose?
When you’re ill, your body releases stress hormones like cortisol and adrenaline. These hormones make the liver release extra glucose, which can raise blood sugar even when you’re not eating.
At the same time, dehydration and reduced insulin absorption can make glucose levels harder to control.
Depending on your condition, you might need to increase or decrease your insulin doses to stay within your target range.
Fever, Cold, or Respiratory Infections
When your body fights infection, it releases hormones that raise blood glucose. This means you often need more insulin than usual.
What to do:
Monitor blood glucose and ketones every 2–4 hours.
Never skip insulin, even if you’re eating less.
If glucose levels stay above 250 mg/dL (14 mmol/L) for more than 4 hours, you may need a correction dose.
Many people require 10–20% more basal insulin during infections or fever.
Drink plenty of fluids — at least 250 ml every hour (water, broth, or sugar-free drinks).
Record glucose readings and doses to share with your healthcare provider.
High blood sugar + illness = always check for ketones.
Stomach Viruses, Nausea, and Vomiting
Stomach illnesses can lower your glucose levels because you eat less or can’t keep food down.
Still, your body needs some insulin to prevent ketone buildup and diabetic ketoacidosis (DKA).
What to do:
Check glucose and ketones every 2–3 hours.
Try to sip fluids that contain carbs (juice, milk, electrolyte solutions) if you can’t eat solid food.
If glucose levels drop, consider slightly reducing basal insulin — but never stop insulin completely.
If vomiting persists or ketones appear, seek medical help right away.
Keep glucose tablets or gel on hand for quick treatment of lows.
Vomiting + high glucose + ketones = possible DKA — emergency situation.
When to Call Your Doctor?
Contact your healthcare team if:
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You have vomiting or diarrhea lasting more than 6 hours.
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Blood glucose remains over 13.9mmol (250 mg/dL) despite correction.
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You have moderate or large ketones in urine or blood.
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You experience shortness of breath, confusion, or severe dehydration.
Always Check for Ketones
When you’re sick, your body may produce ketones, especially if your blood glucose stays high. Always keep ketone test strips or a blood ketone meter at home. Testing for ketones early helps you act fast and prevent serious complications like diabetic ketoacidosis (DKA).
Being active is an important part of life with diabetes. Knowing how sports and exercise affect blood sugar and how to prepare helps you stay confident, safe, and enjoy every game or activity.
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