Managing your diabetes during sick days can be a tough task. Blood glucose levels can be severely impacted when you are sick, and there can be deadly consequences if your blood sugar is not managed carefully.
How Blood Glucose Levels Fluctuate When You Are Sick
When a person who has either type 1 or type 2 diabetes is sick with a cold or the flu, they may experience several diabetes-related symptoms at the same time. The stress from being sick causes your body to release hormones that raise blood glucose levels. This could cause a disruption to your daily activities and how you would normally treat your diabetes.
Insulin resistance also increases when you’re sick. The same hormones that fight illness can also cause insulin to function less effectively, leading to an increase in blood glucose levels.
Blood glucose levels can also decrease or increase when you experience vomiting or diarrhea. Prepare in advance for a sick day by assembling a sick-day kit and establishing a realistic sick-day care plan.
Important Medical Supplies: Your Sick-Day Kit
Put together a sick-day kit that you can easily access in the event of an illness. Gathering these items when you’re feeling well will make it easier to effectively manage your diabetes when you’re not feeling well, or to enlist the help of a family member or loved one if needed.
Store your kit in a bag or zippered case somewhere that is easily accessible, such as under the bathroom sink. Be sure to check expiration dates regularly on your glucose strips, glucose tablets and gels, medications, and batteries. Consider including the following in your sick-day kit:
- a blood glucose meter (BGM) or continuous glucose monitor (CGM)
- glucose strips—check the expiration dates and rotate them into use regularly, since glucose strips do expire
- glucose tablets or gels
- ketone test strips to monitor for diabetic ketoacidosis (DKA)
- batteries
- supplies for your insulin pump, if you use one
- a notepad and pen to track glucose levels, medications taken, and illness events (nausea, vomiting, etc.)
- any other medications you may need, such as cold and flu medications, antacids, or pain relievers
Be sure to check your sick-day kit regularly for expired glucose strips, ketone strips, glucose tablets and gels, medications, and batteries.
Create a Sick-Day Plan
In addition to the sick-day kit, have a plan that you can realistically follow. The plan can be written down and added to your kit so that others can find it and help you follow it if needed. According to the American Diabetes Association (ADA, n.d.-b), this plan should include:
- a list of signs and symptoms that would initiate a call with your healthcare provider
- the name and number of someone who can check in on you when you are sick
- a schedule for when to check your blood sugar and where your glucose meter and strips are kept
- a guide for how and when to adjust your insulin and oral medications
- a guideline for when to use ketone test strips to check for ketones
- meal options that are appropriate for sick days (such as when you’re feeling nauseated, experiencing diarrhea, or don’t feel well enough to get out of bed)
- a list of over-the-counter medications that are safe for you to take; include these medications in your sick-day kit, if possible
- a medical alert card saved on your phone—this is a quick-access summary of your health conditions, medications, allergies, and emergency contacts
- an emergency contact added to your phone’s health information or lock screen settings for use during a crisis
What to Do When You Are Sick
When you are sick, it is important to follow your sick-day plan and have your sick-day kit ready when you need it. You also should:
- Reach out to a friend or relative to let them know you are sick and ask them to stay with you or check in on you regularly.
- Continue taking your diabetes medications—this is essential—unless your healthcare team advises otherwise. Depending on your illness, your healthcare team may advise you to change your intake of medication. Illness can cause your blood sugar to rise or fall unpredictably, so medication remains crucial for maintaining the right balance.
- Be sure to drink lots of fluids to avoid dehydration. If you are having trouble keeping water down, try to take small sips every 15 min throughout the day.
- Make sure you keep water or a zero-calorie drink close by, as it is important to stay hydrated when you’re sick.
- Monitor your blood glucose levels. Have some simple carbs, such as glucose tablets or gels, available to treat low blood glucose levels. To prevent hypoglycemia (blood glucose levels below 70 mg/dl), the 15/15 rule can be used.
The 15/15 Rule
If your blood glucose is below 70 mg/dl, eat 15 g of a fast-acting carbohydrate. Wait 15 min to recheck your blood glucose. If it is still below 70 mg/dl, have another 15 g of carbohydrate and continue to recheck every 15 min until your blood glucose level is back in the normal range.
Having easily accessible nonperishable sources of fast-acting carbohydrates, such as glucose tablets or gels, is important for managing your blood glucose levels and should be included in your sick-day kit (ADA, n.d.-a).
What to Eat When You Don’t Feel Like Eating
Try to consume at least 50 g of carbohydrates every 4 hr, even if you don’t feel like eating. This, combined with maintaining your medication schedule, will help you keep your blood glucose levels within a healthy range.
Some food and drink options when your appetite is poor include:
- canned soup or broth
- instant-cook cereals such as cream of wheat, oatmeal, or grits
- crackers
- instant pudding or premade pudding cups
- gelatin desserts, like Jell-O
- single-serving containers of applesauce or fruit cocktail
- smoothies, premixed protein drinks, or oral nutrition supplements designed for blood sugar management (such as low-glycemic, high-protein shakes)
Remember to choose low-sodium options if needed, and use disposable cutlery and napkins when you are sick to make cleanup easier and reduce the spread of germs (Franciscan Health, 2025).
You can consume the additional items below based on the results of your blood glucose readings. On sick days, it is better to have your blood glucose levels a little too high than too low. Remember that being sick tends to raise blood glucose levels. If you’re not able to eat or keep food down, sipping these drinks in small amounts over the course of the day will provide a steady stream of carbohydrates and help keep your blood glucose from dropping too low.
- regular sports drinks
- regular, non-diet soft drinks
- 100% fruit juice
Diabetic Ketoacidosis
Diabetic ketoacidosis (DKA) is more common in type 1 diabetes than in type 2 diabetes. However, on sick days, all people with diabetes should monitor for DKA. Here’s what you should know about DKA:
- Diabetic ketoacidosis is a life-threatening medical condition where the body, lacking insulin, breaks down fat too quickly, producing acids called ketones.
- The buildup of ketones in the blood causes the blood to become acidic (ketoacidosis), which, without rapid medical intervention, can lead to coma or death.
- High levels of ketones in your urine or your blood can also be an indicator that you are getting sick or that your blood glucose is not well-managed.
Whenever you are sick or your blood glucose levels are above 240 mg/dl, check for ketones in your blood or urine. The ADA recommends testing ketones every 4 to 6 hr when you are feeling sick. You can do this with a simple over-the-counter home testing kit. Testing kits can check for ketones in either blood or urine (ADA, n.d.-b).
Signs and Symptoms of Diabetic Ketoacidosis
In addition to testing blood or urine every 4 to 6 hr for ketones, the Cleveland Clinic (2024) provides the following list of symptoms to watch for:
- excessive thirst or very dry mouth
- frequent urination
- high blood glucose levels: 240 mg/dl or higher
- feeling extremely tired
- skin that is dry or flushed
- nausea, vomiting, or abdominal pain
- difficulty breathing
- fruity odor on breath
- confusion or extreme lack of focus
When to Call the Doctor
It is important to contact your healthcare provider if your symptoms worsen or do not respond to treatment. Contact your healthcare provider if you experience any of these symptoms:
- large amounts of ketones in your urine
- For most urine test strips, the guide on the bottle is color-coded to indicate trace, low, moderate, and high amounts of ketones detected.
- If the color code indicates that ketones are getting into the high range, contact your healthcare provider.
- blood glucose level under 60 mg/dl or over 300 mg/dl
- difficulty breathing
- a fever over 101 °F for 24 hr
- trouble thinking or staying awake
- inability to keep liquids down for more than 4 hr
- vomiting and diarrhea for more than 6 hr
- inability to eat normally for more than 24 hr
Summary
Managing diabetes while you’re sick can be challenging, but it’s easier when you’re prepared. Be prepared for sick days by identifying a family member or loved one who knows your care plan and can assist you.
Build a sick-day kit with all the items you may need to manage your diabetes while you’re sick, and store it somewhere that is easily accessible. Discuss your sick-day plan with your healthcare provider in advance, including how to monitor and treat your blood glucose and ketones.
Remember to take your medications as directed and follow the 15/15 rule for treating hypoglycemia. Reach out to your healthcare provider if you experience concerning symptoms or are unable to manage your blood glucose.
References
American Diabetes Association. (n.d.-a). Getting sick: If you get sick, know what to do. Retrieved August 26, 2025, from https://diabetes.org/getting-sick-with-diabetes/coronavirus-covid-19/know-what-to-do
American Diabetes Association. (n.d.-b). Getting sick: Planning for sick days. Retrieved August 26, 2025, from https://diabetes.org/getting-sick-with-diabetes/sick-days
Cleveland Clinic. (2024, June 27). Diabetes-related ketoacidosis (DKA). Retrieved June 30, 2025, from https://my.clevelandclinic.org/health/diseases/21945-diabetic-ketoacidosis-dka
Franciscan Health. (2025, November 21). Managing diabetes on sick days. Franciscan Alliance Inc. https://www.franciscanhealth.org/community/blog/diabetes-sick-days
