When you're dealing with an illness—whether it's a common cold, the flu, a stomach bug, or any other infection—managing your blood sugar levels becomes significantly more challenging. For people living with diabetes, understanding how to navigate sick days is not just helpful; it's essential for preventing serious complications and maintaining overall health. This comprehensive guide will walk you through everything you need to know about keeping your blood sugar in check when illness strikes.
Why Illness Affects Blood Sugar Levels
When you're sick with the flu or another illness, your body releases hormones to fight infection, and these hormones raise blood sugar levels. This physiological response is part of your body's natural defense mechanism, but it creates unique challenges for people with diabetes.
During stressful situations, epinephrine (adrenaline), glucagon, growth hormone and cortisol play a role in blood glucose levels, particularly during infections, serious illness or significant emotional stress. When stressed, the body prepares itself by ensuring that enough sugar or energy is readily available—insulin levels fall, glucagon and epinephrine levels rise and more glucose is released from the liver, while growth hormone and cortisol levels rise, causing body tissues to be less sensitive to insulin, resulting in more glucose available in the bloodstream.
These hormones make it hard for insulin or other medicines to lower your blood sugar. Even if you're eating less than usual or have no appetite at all, your blood glucose can still climb to dangerous levels. While having diabetes does not make you more likely to get a cold or flu, it does raise your chances of getting seriously sick.
Creating Your Sick Day Action Plan
The best time to prepare for illness is before you get sick. Work with your doctor to write a sick-day plan for how to help prevent high blood sugar when you're sick, keep your plan in a handy place, and let your family know where you keep the plan. Having a written plan eliminates guesswork during a time when you may not be thinking clearly.
Essential Components of Your Sick Day Plan
Before you get sick, decide on an action plan with your health care team that includes when to call your doctor (in most cases if you are vomiting or have diarrhea more than three times over 24 hours or have had a fever over 101° for 24 hours), how often to check your blood glucose, what foods and fluids to take during your illness, how to adjust your insulin or oral medication if needed, and if and when you need to check for ketones.
Discuss what over the counter medications you should use for colds, flu, etc., as some can raise your blood glucose or affect your usual medications. Many common cold and flu remedies contain ingredients that can interfere with diabetes management, so it's crucial to know which products are safe for you to use.
After you've discussed these topics with your diabetes care team, be sure to write your plan down to reference when you're feeling sick, and keep a list of emergency information such as your doctor's phone number, a list of medications you're taking, and your insurance information.
Building Your Sick Day Supply Kit
Assembling a sick day kit ahead of time ensures you have everything you need when illness strikes. Your kit should include both medical supplies and appropriate foods and beverages.
It is a good idea to make a sick-day plan before you get sick by keeping sugar-free liquids and liquids with 15 grams of carbohydrates in your home, and having urine ketone test strips in your home that are not expired. Stock up on items like sugar-free beverages, regular gelatin, sports drinks, crackers, applesauce, and broth-based soups.
Your sick day kit should also include a thermometer, extra blood glucose testing supplies, ketone testing strips (especially important for people with type 1 diabetes), and a written copy of your sick day plan with emergency contact numbers.
Monitoring Blood Sugar During Illness
Frequent blood sugar monitoring becomes even more critical when you're sick. Check your blood sugar more often than usual (every 2 to 4 hours), try to keep your blood sugar at less than 200 mg/dL, and there may be times when you need to check your blood sugar every hour.
Test your blood sugar at least every 3 to 4 hours, and check it more often, even through the night, if it goes up fast. This frequent monitoring helps you catch dangerous trends early and allows you to respond appropriately with medication adjustments or by seeking medical attention.
Keeping Accurate Records
Write down or record all your blood sugar levels, the time of each test, and the medicines you have taken. This documentation is invaluable if you need to contact your healthcare provider or seek emergency care. It provides a clear picture of how your blood sugar has been behaving and what interventions you've already tried.
Consider using a continuous glucose monitoring (CGM) system if you have access to one. During illness, check your blood sugar every two to four hours with recommended CGM sensors, and if levels are unstable, check more often, as nighttime checks may also be necessary. CGM devices can alert you to dangerous trends even while you're sleeping, providing an extra layer of safety during illness.
Managing Medications When You're Sick
One of the most common mistakes people with diabetes make when they're sick is stopping their medications. This can be extremely dangerous and lead to serious complications.
Continue Taking Your Diabetes Medications
Take your diabetes medicines as usual, and keep taking your diabetes medicine, even if you vomit and have trouble eating or drinking. This is crucial because your body is producing stress hormones that raise blood sugar, so you need your medications to counteract this effect.
Continue taking your insulin and diabetes pills as usual, and test your blood sugar every 4 hours and keep track of the results. Even if you're not eating normally, your blood sugar can still rise significantly due to the stress response.
If you are vomiting and can't take your medicine, call your doctor, as you may need to adjust your medicines. Never make major medication changes on your own without consulting your healthcare provider first.
When Medication Adjustments May Be Necessary
If you cannot eat your normal amount of carbohydrates, use your sick day plan or contact your provider, as you may need to make a change in your insulin dose or in the dose of your diabetes pills or other injections, especially if your illness is making your blood sugar higher than normal.
For people who use insulin pumps, do not take off your pump unless you will be taking insulin shots while you are off the pump. Removing your pump without an alternative insulin delivery method can quickly lead to dangerous blood sugar elevations and ketone development.
The Critical Importance of Hydration
Staying properly hydrated is one of the most important aspects of sick day management for people with diabetes. Dehydration can worsen high blood sugar levels and lead to serious complications.
How Much to Drink
Drink plenty of sugar-free fluids to keep your body from getting dehydrated, aiming for at least twelve 8-ounce cups (3 liters) of fluid a day. This may seem like a lot, especially when you're feeling unwell, but adequate hydration is essential for helping your body process glucose and fight infection.
Be sure you're getting enough water—so drink plenty of it, and if you're having trouble keeping water down, have small sips every 15 minutes or so throughout the day. Small, frequent sips are often easier to tolerate than trying to drink large amounts at once.
Choosing the Right Fluids
The type of fluids you should drink depends on your current blood sugar level. If your blood sugar level is higher than the level your doctor recommends (for example, 240 mg/dL), drink extra liquids that don't contain sugar, such as water or sugar-free cola. Sugar-free options include water, sugar-free gelatin, diet caffeine-free soda, clear broth, and sugar-free popsicles.
If your blood sugar is less than 100 mg/dL or falling quickly, it is OK to drink fluids that have sugar in them, and try to check their effect on your blood sugar in the same way you check how other foods affect your blood sugar. In these situations, regular soda, fruit juice, sports drinks, or regular gelatin can help prevent dangerous lows while keeping you hydrated.
Prevent dehydration by drinking plenty of fluids, including water and caffeine free, sugar free beverages. Avoid caffeinated beverages as they can promote dehydration and make it harder to maintain stable blood sugar levels.
Nutrition Strategies for Sick Days
Eating when you're sick can be challenging, but maintaining some carbohydrate intake is important for preventing dangerous blood sugar swings and supporting your body's healing process.
When You Can't Eat Regular Meals
If you can't eat meals, you'll need to eat or drink about 50 grams of carbohydrates every 4 hours, with some examples including 1½ cup of unsweetened applesauce or 1½ cup of fruit juice. This helps prevent your blood sugar from dropping too low while also providing your body with the energy it needs to fight illness.
If you can't eat your usual foods, drink extra liquids, such as soup, sports drinks, or milk, and you may also eat food that's gentle on your stomach, such as bananas, rice, crackers, gelatin, or applesauce. These bland, easily digestible foods are less likely to upset your stomach while still providing necessary carbohydrates.
Eat small meals often, and even if you are not eating as much, your blood sugar can still get very high. Small, frequent meals are often easier to tolerate than three large meals when you're feeling unwell.
Managing Nausea and Vomiting
If you throw up, do not drink or eat anything for 1 hour, rest but do not lie flat, and after 1 hour, take sips of soda such as ginger ale every 10 minutes—if vomiting persists, contact or see your provider. Persistent vomiting can quickly lead to dehydration and dangerous blood sugar fluctuations.
For people with diabetes, nausea and vomiting present a particular challenge because you need to maintain some carbohydrate intake to prevent low blood sugar, but you also need to avoid overwhelming your digestive system. Start with very small amounts and gradually increase as tolerated.
Understanding and Testing for Ketones
Ketone testing is a critical component of sick day management, especially for people with type 1 diabetes. If your body doesn't have enough insulin, it starts breaking down fat as fuel, which produces a byproduct called ketones. High levels of ketones in the blood can lead to diabetic ketoacidosis (DKA), a life-threatening emergency.
When to Check for Ketones
If you take insulin, do a test for ketones, especially when you have high blood sugar, and some home blood sugar meters can also measure blood ketones. Ketone testing is particularly important when your blood sugar is elevated during illness.
If you have type 1 diabetes check your urine for ketones when your blood sugar is 300 or higher, and call your doctor if you have moderate to high ketones in your urine or high blood sugars over 300 on two tests in a row that does not respond to insulin and fluids. Moderate to large ketones require immediate medical attention.
If you have type 1 diabetes, check your urine ketones every time you urinate. This frequent monitoring during illness helps catch ketone development early, before it becomes dangerous.
What Ketone Results Mean
Ketone test results typically come in ranges: negative, trace, small, moderate, and large. Negative to small ketones may be manageable at home with increased fluids and insulin adjustments according to your sick day plan. However, moderate to large ketones are considered a medical emergency and require immediate contact with your healthcare provider or emergency services.
Understanding how to interpret ketone results and when to seek help can literally be lifesaving. Never ignore moderate or high ketone readings, even if you're feeling relatively okay. Ketoacidosis can progress rapidly and become life-threatening within hours.
Recognizing Warning Signs and When to Seek Help
Being sick increases the risk of more serious emergencies seen with diabetes. Knowing when to contact your healthcare provider or seek emergency care is crucial for preventing serious complications.
When to Call Your Doctor
Minor illnesses in people with diabetes (especially children with type 1 diabetes) can lead to very high blood sugar levels and possible emergencies, so when children are sick, watch them closely for signs that they need medical attention right away, and your doctor will tell you what signs to watch for and what blood sugar level they recommend.
If your provider does not contact you back right away, you may need to go to the emergency room, particularly if you are vomiting or have diarrhea for more than 4 hours. Don't hesitate to seek emergency care if you're unable to reach your regular healthcare provider and symptoms are worsening.
Emergency Warning Signs
Go to the emergency room right away if any of the following occurs: you're having trouble breathing, you have ketones in your urine, you can't keep any liquids down for more than 4 hours or can't keep food down more than 24 hours, you lose 5 pounds or more during the illness, your blood sugar is lower than 60 mg/dl, or you have vomiting and/or severe diarrhea for more than 6 hours.
Other warning signs that require immediate medical attention include confusion or difficulty thinking clearly, rapid breathing, fruity-smelling breath (a sign of ketoacidosis), severe abdominal pain, and persistent high blood sugar that doesn't respond to your usual interventions.
Additional Monitoring During Illness
Beyond blood sugar and ketone monitoring, there are other important health indicators to track when you're sick with diabetes.
Temperature Monitoring
Check your temperature every morning and evening, as a fever may be a sign of infection. Tracking your temperature helps you and your healthcare provider understand the severity of your illness and whether it's improving or worsening.
A fever indicates that your body is fighting an infection, which means stress hormones are likely elevated and affecting your blood sugar. Higher fevers generally correlate with more significant blood sugar elevations and may require more aggressive management.
Weight Monitoring
Weigh yourself every day, as losing weight without trying is a sign of high blood sugar. Unexplained weight loss during illness can indicate that your body is breaking down fat and muscle for energy because glucose isn't getting into your cells properly—a sign of inadequate insulin.
Daily weighing also helps you monitor for dehydration. Rapid weight loss over a day or two is often due to fluid loss, which requires immediate attention through increased fluid intake or, in severe cases, intravenous fluids.
Special Considerations for Different Types of Diabetes
While the general principles of sick day management apply to all people with diabetes, there are some specific considerations depending on your type of diabetes and treatment regimen.
Type 1 Diabetes
People with type 1 diabetes face particular risks during illness because their bodies produce no insulin at all. This makes ketone development more likely and potentially more rapid. Ketone testing should be done more frequently, and any elevation in ketones requires prompt action.
Never stop taking basal (long-acting) insulin, even if you're not eating. Your body needs this background insulin to prevent ketone formation. You may need additional rapid-acting insulin to correct high blood sugars and treat ketones, following your sick day plan or your healthcare provider's guidance.
Type 2 Diabetes
People with type 1 diabetes or type 2 diabetes may experience unpredictable blood sugar levels during illness. For those with type 2 diabetes who don't take insulin, ketone development is less common but still possible, especially during severe illness.
If you don't take insulin, continue to take your diabetes medications, even if you are sick and have been throwing up. Some oral medications may need adjustment during illness, but this should only be done under your healthcare provider's guidance.
Managing Stress and Rest
The physical stress of illness is compounded by the mental and emotional stress of managing diabetes during this challenging time. Both types of stress can affect your blood sugar levels.
The Importance of Rest
Adequate rest is essential for recovery from any illness. Your body needs energy to fight infection and heal, and rest helps conserve that energy. While it's important to monitor your blood sugar frequently, try to rest between checks and avoid unnecessary activity.
However, if you're experiencing high blood sugar, gentle movement like walking slowly around your home can sometimes help lower glucose levels. Balance rest with light activity based on how you're feeling and your blood sugar readings.
Reducing Stress
The stress of being sick combined with the worry about blood sugar management can create a vicious cycle where stress hormones further elevate blood glucose. Try to stay calm and remember that you have a plan in place. Deep breathing exercises, meditation, or listening to calming music can help reduce stress levels.
Don't hesitate to ask for help from family members or friends. Having someone assist with blood sugar monitoring, meal preparation, or medication management can reduce your stress and ensure you don't miss important tasks when you're feeling unwell.
Over-the-Counter Medications and Diabetes
Don't take any nonprescription medicines unless you talk to your doctor first, as many nonprescription medicines can affect your blood sugar level. This is a critical point that many people overlook when treating common cold and flu symptoms.
Medications That Can Affect Blood Sugar
Many over-the-counter cold and flu medications contain ingredients that can raise blood sugar levels. Decongestants, particularly those containing pseudoephedrine or phenylephrine, can elevate blood glucose. Some cough syrups and liquid medications contain significant amounts of sugar or alcohol.
Corticosteroids, sometimes prescribed for severe respiratory infections or inflammation, can cause significant blood sugar elevations. If your doctor prescribes a steroid medication, make sure they know you have diabetes so they can help you adjust your diabetes medications accordingly.
Safer Alternatives
Ask your pharmacist or healthcare provider to recommend diabetes-friendly options for treating cold and flu symptoms. Sugar-free cough drops, acetaminophen or ibuprofen for fever and pain (if not contraindicated), and saline nasal sprays are generally safer choices for people with diabetes.
Always read medication labels carefully, looking for sugar content and active ingredients that might affect blood glucose. When in doubt, call your healthcare provider or pharmacist before taking any new medication, even if it's available without a prescription.
Prevention: Reducing Your Risk of Illness
While you can't prevent every illness, there are steps you can take to reduce your risk of getting sick in the first place.
Vaccinations
You'll also want to be sure to get your annual flu shot to make getting the flu less likely. Vaccinations are particularly important for people with diabetes because they're at higher risk for complications from preventable illnesses.
In addition to the annual flu vaccine, people with diabetes should stay current on pneumonia vaccines, COVID-19 vaccines and boosters, and other recommended immunizations. Talk to your healthcare provider about which vaccines are appropriate for you based on your age, overall health, and diabetes management.
Good Hygiene Practices
Basic hygiene practices can significantly reduce your risk of infection. Wash your hands frequently with soap and water for at least 20 seconds, especially before eating, after using the bathroom, and after being in public places. Use hand sanitizer when soap and water aren't available.
Avoid touching your face, particularly your eyes, nose, and mouth, as these are entry points for viruses and bacteria. Stay away from people who are obviously sick when possible, and if you must be around someone who's ill, maintain distance and consider wearing a mask.
Maintaining Good Blood Sugar Control
Ironically, one of the best ways to reduce your risk of complications from illness is to maintain good blood sugar control when you're well. Consistently high blood sugar levels can weaken your immune system, making you more susceptible to infections and less able to fight them off effectively.
Work with your healthcare team to optimize your diabetes management year-round. This includes taking medications as prescribed, following a healthy eating plan, staying physically active, getting adequate sleep, and managing stress. Good baseline control makes it easier to manage blood sugar during the inevitable times when you do get sick.
Special Situations: Surgery, Dental Work, and Injuries
A sick day can be caused by a cold, flu, surgery, infection, injury, stress or dental work. It's important to recognize that "sick day" management principles apply to more than just infectious illnesses.
Planned Procedures
If you're scheduled for surgery or a dental procedure, talk to both your diabetes healthcare provider and the provider performing the procedure well in advance. You may need special instructions about when to take your diabetes medications, whether you need to fast, and how to manage your blood sugar before, during, and after the procedure.
Even minor dental work can cause stress that affects blood sugar levels. Some dental procedures may require antibiotics, which can also impact blood glucose. Plan ahead and monitor your blood sugar more frequently around any medical or dental procedure.
Injuries and Wounds
Injuries, even minor ones, trigger the same stress response as illness. Cuts, burns, sprains, or other injuries can cause blood sugar to rise. Additionally, high blood sugar can slow wound healing and increase infection risk, creating a problematic cycle.
If you sustain an injury, monitor your blood sugar more frequently and watch the wound carefully for signs of infection such as increased redness, warmth, swelling, or drainage. Seek medical attention promptly if a wound isn't healing properly or shows signs of infection.
Long-Term Considerations After Illness
Once you've recovered from your illness, there are a few important follow-up steps to take.
Reviewing Your Sick Day Management
After you're feeling better, schedule a follow-up appointment with your healthcare provider to review how your sick day went. Discuss what worked well and what could be improved. This information helps refine your sick day plan for future illnesses.
If you had difficulty managing your blood sugar, needed emergency care, or developed ketones, it's especially important to review these events with your healthcare team. They may recommend adjustments to your sick day plan or changes to your regular diabetes management regimen.
Replenishing Your Sick Day Kit
After an illness, restock any supplies you used from your sick day kit. Replace expired ketone test strips, refill medications, and restock foods and beverages. You want to be prepared for the next time illness strikes, which hopefully won't be soon but could happen at any time.
Monitoring for Diabetes Development
Interestingly, severe illness can sometimes unmask previously undiagnosed diabetes or prediabetes. If you experienced unusually high blood sugar during an illness but don't have a diabetes diagnosis, follow up with your healthcare provider. They may recommend testing to determine if you have diabetes or are at risk for developing it.
Resources and Support
Managing diabetes during illness can feel overwhelming, but you don't have to do it alone. Numerous resources are available to help you navigate sick days successfully.
Healthcare Team Support
Your diabetes healthcare team is your primary resource for sick day management. This team may include your primary care physician, endocrinologist, diabetes educator, dietitian, and pharmacist. Make sure you have contact information for all team members and know how to reach them during evenings, weekends, and holidays.
Many healthcare systems now offer telehealth options, which can be particularly helpful when you're sick and don't feel well enough to travel to an appointment. Ask your healthcare provider about virtual visit options for sick day guidance.
Educational Resources
Organizations like the American Diabetes Association (https://www.diabetes.org), the Centers for Disease Control and Prevention (https://www.cdc.gov/diabetes), and JDRF (for type 1 diabetes) offer extensive educational materials about sick day management. These resources include printable sick day plans, carbohydrate counting guides, and information about when to seek emergency care.
Diabetes education programs, whether in-person or online, can provide comprehensive training on sick day management and other aspects of diabetes care. Many insurance plans cover diabetes self-management education, so check with your insurer about available programs.
Support Groups and Communities
Connecting with others who have diabetes can provide emotional support and practical tips for managing sick days. Online communities, local support groups, and diabetes camps or conferences offer opportunities to learn from others' experiences and share your own.
Hearing how others have successfully navigated illness while managing diabetes can boost your confidence and provide new strategies you might not have considered. Just remember that everyone's diabetes is different, so what works for someone else may need to be adapted for your situation.
Key Takeaways for Sick Day Success
Successfully managing blood sugar during illness requires preparation, vigilance, and knowing when to ask for help. Here are the most important points to remember:
- Prepare before you get sick by creating a written sick day plan with your healthcare team, assembling a sick day supply kit, and making sure your family knows where to find your plan and emergency contact information.
- Monitor more frequently by checking blood sugar every 2-4 hours (or more often if needed), testing for ketones when blood sugar is elevated (especially if you have type 1 diabetes), and keeping detailed records of all readings and medications taken.
- Never stop your diabetes medications unless specifically instructed by your healthcare provider, even if you're not eating normally, as illness causes stress hormones that raise blood sugar.
- Stay hydrated by drinking plenty of fluids—sugar-free options when blood sugar is high, and fluids containing carbohydrates if blood sugar is low or falling rapidly.
- Maintain carbohydrate intake through easily digestible foods and beverages, aiming for about 50 grams of carbohydrates every 4 hours if you can't eat regular meals.
- Know when to seek help by recognizing warning signs like persistent vomiting or diarrhea, moderate to large ketones, blood sugar that won't respond to treatment, difficulty breathing, or confusion.
- Be cautious with over-the-counter medications as many can affect blood sugar levels—always check with your healthcare provider or pharmacist before taking any new medication.
- Prevent illness when possible through vaccinations, good hygiene practices, and maintaining optimal blood sugar control when you're well.
Conclusion
Managing blood sugar during illness is one of the more challenging aspects of living with diabetes, but with proper preparation and knowledge, you can navigate sick days safely and effectively. When you have diabetes, it's a little more difficult to manage an illness, and even something as simple as a cold can make your routine feel harder to follow, but when you know what to do when illness hits, you can stay safe, recover faster and avoid serious complications.
The key is preparation. Don't wait until you're sick to think about how you'll manage your diabetes. Work with your healthcare team now to create a comprehensive sick day plan, assemble your supply kit, and make sure you understand when to seek help. Review and update your plan regularly, especially if your diabetes management regimen changes.
Remember that every illness is different, and what works for one sick day may need adjustment for another. Stay flexible, monitor closely, and don't hesitate to reach out to your healthcare team when you're unsure about what to do. With the right preparation and support, you can successfully manage your blood sugar through illness and get back to feeling your best.
Your health and safety are the top priorities. When in doubt, it's always better to contact your healthcare provider or seek emergency care rather than waiting to see if things improve on their own. Trust your instincts—you know your body and your diabetes better than anyone else. Stay prepared, stay vigilant, and take care of yourself.