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Diabetes Sick Days

When you have diabetes, sick days often mean more than a runny nose and sneezing. An illness such as a cold or the flu, or any condition resulting in nausea, vomiting, or diarrhea, may cause your blood sugar to increase. An infection can also raise blood sugar levels. Therefore, it is very important to test your blood sugar when you are sick. Here are some guidelines to follow when you are ill:

  • Check your blood sugar every four hours.
  • Test for ketones if your blood sugars are above 240mg/dL, or as directed by your health care provider. Ketones are a form of waste often produced in the bodies of people with type 1 diabetes when they are under stress (such as during an illness). Call your doctor if ketones are found in your urine. Depending on the degree of your illness, he or she may suggest that you go to the emergency room.
  • Check your temperature regularly.
  • Make sure you are drinking liquids if you are unable to keep down solid food. Drink one cup of liquid every hour while you are awake to prevent dehydration. If you are unable to hold down liquids, you may need to go to the emergency room or hospital.
  • Do not stop taking insulin, even if you are unable to eat solid foods. You may need to eat or drink something with sugar in some form so that your blood sugar doesn't drop too low. People with type 2 diabetes who are on oral medicines may need to stop taking their medication when sick. Check with your doctor if you are unsure of what to do.
  • If you need an over-the-counter drug to control symptoms such as cough and nasal congestion, ask your doctor or pharmacist for a list of sugar-free products that are available.

When Should I Call My Doctor?

If you have diabetes and are sick, call your doctor if:

  • Your blood sugar stays higher than 180 mg/dL or lower than 70 mg/dL.
  • You are unable to keep liquids or solids down.
  • You have a fever (temperature over 101 F).
  • You have diarrhea or are vomiting.


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If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

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