Illness comes in many forms, and can affect everyone in different ways. Unfortunately, sickness can disrupt not only your usual daily routine, but also make your glucose levels more unpredictable. In particular, a surge in stress hormones can raise blood glucose and make your body less responsive to the effects of insulin, while poor appetite and nausea/vomiting can disrupt normal eating patterns and digestion.
It can be helpful to take a step back and understand that insulin plays a critical role in how your body distributes and processes its nutrients. When glucose supplies are plentiful, your pancreas normally releases insulin in higher quantities to direct the flow of glucose from the bloodstream into your cells, either for immediate use as energy or for storage (e.g. as glycogen and fat). At the same time, insulin also prevents the breakdown of fats, reserving them for times of need.
Unfortunately, when your body already doesn’t make enough insulin, you need more of it when you’re ill. This can create the perfect storm, whereby insulin activity wanes, glucose can no longer enter your cells, and levels in your blood begin to rise unchecked. Dehydration and electrolyte imbalance occurs as high glucose levels spill into the urine and drag water along with it. Meanwhile, your body shifts towards burning fat instead of glucose for energy, resulting in the release and accumulation of ketones. Ketones are a byproduct of fat breaking down. Ketones are used as an alternative energy source but are also acidic and lower the pH of your blood, which can cause basic body processes to stop functioning properly.
The goal of sick day management in diabetes is ultimately to avoid this potentially life-threatening condition, known as diabetic ketoacidosis, which occurs more commonly in type 1 diabetes but can also occur in type 2 diabetes.
Things To Do
- Continue your basal insulin. Even though you may be less active, your body still needs basal insulin to maintain glucose levels in the normal range. Omitting your basal insulin is dangerous and can be life threatening.
- Use your fast/rapid-acting insulin when eating and for corrections. Use bolus insulin when eating (may require more than typical doses, but intake may also be reduced) and for corrections (may require a 10–20% increase if blood sugar not responding).
- Drink plenty of fluids. Staying hydrated during illness is good advice in general, but is especially important for those of us with diabetes. You should drink at least one cup of water per hour, being careful about any added sugars (although a limited amount of sugar may be warranted if your BG is running low). A good marker of adequate hydration is the quantity and quality of your urine—if you haven’t needed to urinate for a few hours or your urine is very concentrated (e.g. dark yellow or brown), you probably aren’t drinking enough.
- Monitor your BG closely. Check your BG at least every 4 hours; check ketones every 4–6 hours if not feeling well and/or blood sugar > 250mg/dL (note that urine ketone strips expire 6 months after opening); hydrate generously, at least one cup of water per hour (limited sugar may be warranted if blood sugars running low).
- For patients on pumps, consider using injections as a more reliable alternative if insulin pump not effectively controlling blood sugar
- Be careful of over-the-counter sugar-containing remedies and the impact they can have on blood sugar
Reasons to Seek Medical Attention
- BG persistently above 250mg/dL (especially if two or more correction boluses have been ineffective) with thirst, excessive urination, or very concentrated urine
- High ketone levels (measured in urine or blood)
- Uncontrolled vomiting, diarrhea, and/or an inability to keep food down