Getting “real people” sick with type 1 diabetes inevitably comes with a variety of extra concerns because a severe virus, cold, or infection can have a big impact on your blood sugar and your insulin needs.

In this article, we’ll discuss the need-to-know details of managing type 1 diabetes and your overall wellbeing when you come down with a cold, the flu, or a stomach virus.

Type 1 diabetes when you are sick

During a cold

The most likely effect a cold will have on your diabetes will be insulin resistance, which means you may need to temporarily increase your background/basal insulin dose. 

The increase may be anywhere from 10 to 25 percent of your usual total background/basal insulin needs, suggests Gary Scheiner, CDE from  Integrated Diabetes.

This is an important decision to make with your healthcare team — which means calling them when you realize your illness is affecting your diabetes.

You may find you also need more rapid-acting insulin with meals.

If you notice that your blood sugars are stubbornly high, talk to your healthcare team about making an adjustment in your insulin doses.

Of course, if your cold has a severe impact on your appetite, and you’re eating significantly less than usual, you may find you actually need to decrease your basal/background insulin. 

Regarding medications, try to use sugar-free cough drops and confirm with the pharmacist that any other cold medications are sugar-free.

During the flu

At the very beginning of the flu, you can ask your doctor for a prescription for a newly approved medication called Xofluza, designed to help prevent the flu from fully establishing especially in people for whom the flu can be very dangerous — like people with diabetes!

For a more traditional bout of the flu — which involves a fever, full-body aches, and exhaustion — it’s important to work with your healthcare team because fighting a severe virus like the flu can lead to ketoacidosis.

If you don’t address those ketones early on, it can escalate into full-blown diabetic ketoacidosis which can be life-threatening and land you in the hospital.

  • Take acetaminophen or ibuprofen to manage your fever, as directed by your doctor.
  • Drink plenty of water — all day long! 
  • Check your temperature — anything over 101 degrees should warrant a call to your doctor.
  • Check your blood sugar often — anything persistently over 240 mg/dL should warrant a call to your doctor.
  • Sip on watered-down Gatorade. It’s important that your body gets some carbohydrates along with adequate insulin, especially if you aren’t eating very much food.
  • Make sure to eat! If you don’t eat or drink some carbohydrates, you will develop starvation ketones on top of illness-induced ketones. This can escalate and become dangerous.
  • Test your ketones morning and night with urine strips.
  • If you test for “small” ketones (light pink on the strip): eat some carbohydrates, take your insulin as prescribed, and drink plenty of fluids!
  • If you test for “moderate” to “large” ketones, contact your healthcare team. They may advise you to take a small bolus of insulin to help eliminate the ketones (even if your blood sugar isn’t high).
  • If you test for “large” ketones and begin feeling nauseous, visit your nearest emergency or urgent care center.
  • If your blood sugars become too stubborn to manage at home, visit your nearest emergency or urgent care center. 

During a stomach virus (with vomiting)

While vomiting once or twice from a rotten Deviled Egg isn’t usually a big deal, a stomach virus for a person with type 1 diabetes can become life-threatening if it isn’t handled quickly and properly.

If you begin vomiting and cannot keep down fluids or glucose tabs, you could experience severe low blood sugar while the fast or rapid-acting insulin you recently dosed for your last meal is still active in your bloodstream without any food to absorb. 

If you begin vomiting and cannot keep fluids down, but you do not have excessive insulin on board, the next obstacle you will face is eventual diabetic ketoacidosis due to severe dehydration along with starvation ketones from your inability to eat.

In either situation, when you are repeatedly vomiting and unable to drink water to rehydrate, you need to visit the nearest emergency room to receive intravenous fluids: a combination of lactated ringers (saline, electrolytes, etc.), and possibly glucose or insulin depending on the state of your blood sugar when you arrive.

  • Gatorade (with or without sugar)
  • Apple juice, ginger ale, etc.
  • Pedialyte

Buy these things now — find the full suggestion list from the U.S. Centers for Disease Control and Prevention (CDC). Do not wait until you are sick and struggling to manage diabetes on top of a stomach virus. Collect these items now and store them with other medical supplies as part of your sick day management toolkit.

IMPORTANT: You still need to take your background/basal insulin when you are vomiting — as recommended by the National Institute of Diabetes, Digestive, and Kidney Diseases (NIDDK). As a person with type 1 diabetes, you will need to call your healthcare team to adjust your medications but you still need some insulin in your system at all times like every other day of your life.

You should have a glucagon kit on-hand for flu & stomach bug season.

Even if you’ve never needed to use a glucagon kit before, it can be life-saving (and panic-reducing) if you suddenly come down with a severe stomach bug. 

A glucagon kit contains a hormone that tells your liver to release glycogen (stored glucose) which is then converted into glucose and raises your blood sugar.

If you start vomiting up the large dinner you just ate and your blood sugar begins to plummet because of the insulin you took for that meal, glucagon can save your life and make it a much calmer trip to the emergency room when you head there for intravenous fluids to rehydrate after puking.

Tip: If you’re conscious and using a glucagon kit on yourself, you don’t likely need the entire full dose of the glucagon kit. Instead, you can use a syringe to withdraw 10 or 20 units to treat your oncoming low blood sugar and then head to the hospital (with a friend to drive, or via ambulance).

What about anti-vomit medications like Zofran?

These medications are designed with good intentions, but unless you’re taking the kind that’s inserted anally, it’s most likely going to come right back up when you vomit. If you’re battling a true stomach virus, Zofran won’t be properly digested in order to prevent you from vomiting. 

Instead, they’re more effective when used with pregnancy-related nausea or sea-sickness.

Talk to your doctor about insulin dose adjustments

Above all else, talk to your doctor about making adjustments to your insulin doses during a significant illness. While a runny nose won’t likely change your insulin needs, anything else can cause you to need more or less insulin depending on a variety of variables.

If you aren’t eating your usual meals, you won’t need to take your usual fast or rapid-acting insulin doses. And you may need to reduce your long-acting/basal insulin dose.

Even after you’ve recovered, you may need to reduce your background insulin doses if your illness causes a weight-loss of even a few pounds.

Check your blood sugar often and work closely with your healthcare team to get through the bout of illness safely!

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