Recognizing and Responding to Illness When You Have Diabetes

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Living with diabetes requires constant vigilance, but when illness strikes, the challenge intensifies significantly. When you have diabetes, other illnesses can make your blood sugar go up, which can be dangerous. Understanding how to recognize the warning signs of blood sugar imbalances during illness and knowing how to respond appropriately can mean the difference between a manageable sick day and a medical emergency. This comprehensive guide will help you navigate the complexities of managing diabetes when you’re feeling under the weather.

Why Illness Affects Blood Sugar Levels

When you’re sick with the flu or another illness, your body releases hormones to fight infection. These hormones raise blood sugar levels. They also make it hard for insulin or other medicines to lower your blood sugar. This physiological response is part of your body’s natural defense mechanism, but for people with diabetes, it creates a unique challenge.

As part of the body’s defence mechanism for fighting illness and infection, more glucose is released into the blood stream. People who don’t have diabetes just produce more insulin to cope. But when you’ve got diabetes, your body can’t do this. This fundamental difference means that even minor illnesses can lead to significant blood sugar fluctuations that require careful monitoring and management.

Being sick can often cause your blood glucose (blood sugar) to be high. It can also affect the way you eat and lower the energy you have to manage diabetes. When you are sick, it may be harder to manage your blood glucose. The combination of elevated stress hormones, changes in eating patterns, and reduced physical activity creates a perfect storm for blood sugar management challenges.

Recognizing Signs of Blood Sugar Imbalance During Illness

Symptoms of High Blood Sugar (Hyperglycemia)

The glucose level at which people with diabetes start to experience symptoms varies. Many people don’t experience symptoms until their blood sugar is 250 mg/dL or higher. Being aware of these symptoms is crucial, especially when you’re already dealing with illness-related discomfort.

Common signs of hyperglycemia include:

  • Increased thirst (polydipsia) and/or hunger, and frequent urination (peeing)
  • Fatigue and weakness
  • Blurred vision
  • Headaches
  • Difficulty concentrating
  • Dry mouth and skin

When illness is present, these symptoms can be easily confused with or masked by the symptoms of your underlying condition, making regular blood sugar monitoring even more critical.

Warning Signs of Diabetic Ketoacidosis (DKA)

If hyperglycemia is left untreated, it can develop into diabetes-related ketoacidosis (DKA), in which a lack of insulin and a high amount of ketones cause your blood to become acidic. DKA can also affect people who have undiagnosed Type 1 diabetes. This condition is an emergency situation that can lead to coma or death.

Critical warning signs of DKA include:

  • Nausea and vomiting, dehydration, abdominal pain, fruity-smelling breath, and deep labored breathing or hyperventilation (Kussmaul breathing)
  • Confusion or difficulty concentrating
  • Extreme fatigue
  • Flushed, hot, dry skin

Severe DKA that goes untreated can cause coma or death. If you experience any of these symptoms, seek emergency medical attention immediately.

Symptoms of Low Blood Sugar (Hypoglycemia)

While illness typically raises blood sugar levels, hypoglycemia can also occur, particularly if you’re unable to eat normally but continue taking your regular diabetes medications. Symptoms of low blood sugar include:

  • Shakiness or trembling
  • Sweating and chills
  • Rapid heartbeat
  • Dizziness or lightheadedness
  • Hunger
  • Irritability or mood changes
  • Confusion or difficulty thinking clearly
  • Weakness or fatigue

Creating Your Sick Day Action Plan

Before you get sick, decide on an action plan with your health care team. This plan should include the following: 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 you need to.

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 this plan prepared in advance ensures that you won’t have to make critical decisions while feeling unwell.

Essential Components of Your Sick Day Plan

Your personalized sick day plan should include:

  • Target blood sugar ranges during illness
  • How often to check blood sugar levels
  • When and how to test for ketones
  • Medication adjustment guidelines
  • List of approved over-the-counter medications
  • Emergency contact numbers for your healthcare team
  • When to seek emergency medical care
  • Specific instructions for your type of diabetes (Type 1 or Type 2)

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. You will also want to keep a list of emergency information such as your doctor’s phone number, a list of medications you’re taking, and your insurance information.

Immediate Response Strategies When Illness Strikes

Blood Sugar Monitoring During Illness

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 (11.1 mmol/L). There may be times when you need to check your blood sugar every hour. Write down or record all your blood sugar levels, the time of each test, and the medicines you have taken.

Check your blood glucose every 3 to 4 hours. Write down your numbers. Keeping detailed records helps you and your healthcare provider identify patterns and make necessary adjustments to your treatment plan.

Ketone Testing

If you have type 1 diabetes, check your urine ketones every time you urinate. Check your urine for ketones if your blood glucose is over 240 milligrams (mg) per deciliter (dL). Ketone testing is a critical safety measure that can help you catch dangerous complications before they become severe.

We recommend testing for ketones every four to six hours when you’re feeling sick. If you take insulin, do a test for ketones, especially when you have high blood sugar. Some home blood sugar meters can also measure blood ketones.

Medication Management

Be sure to take your diabetes medications when you are sick unless your physician or advanced practice provider (APP) gives you different instructions. Do not skip your diabetes medications or insulin even if you feel too sick to eat. This is one of the most important rules of sick day management and contradicts what many people instinctively want to do.

Continue taking your insulin and diabetes pills as usual. Test your blood sugar every 4 hours and keep track of the results. Your body actually needs insulin during illness, often more than usual, even if you’re not eating normally.

If you are vomiting and can’t take your medicine, call your doctor. You may need to adjust your medicines. Never make major medication adjustments without consulting your healthcare provider, but do have a plan in place for when to contact them.

Hydration and Nutrition

Drink at least twelve 8-ounce (oz) cups (3 liters) of fluid a day. Feeling sick often makes you not want to eat or drink, which, surprisingly, can lead to a higher blood sugar. Proper hydration is essential for helping your body process glucose and fight infection.

Drink plenty of water to prevent dehydration. Try to eat as you normally would. If you’re having trouble keeping food down, focus on small, frequent meals or snacks that are easy to digest.

If you can’t eat meals, you’ll need to eat or drink about 50 grams of carbohydrates every 4 hours. Some examples include 1½ cup of unsweetened applesauce or 1½ cup of fruit juice. This ensures your body has enough fuel to function while preventing dangerous drops in blood sugar.

If your blood sugar is less than 100 mg/dL (5.5 mmol/L) or falling quickly, it is OK to drink fluids that have sugar in them. Try to check their effect on your blood sugar in the same way you check how other foods affect your blood sugar.

Managing Vomiting

If you throw up, do not drink or eat anything for 1 hour. Rest, but do not lie flat. After 1 hour, take sips of soda, such as ginger ale, every 10 minutes. If vomiting persists, contact or see your provider. Persistent vomiting is a serious concern for people with diabetes and requires medical attention.

When to Seek Emergency Medical Care

Knowing when to seek emergency care can be lifesaving. 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. You have vomiting and/or severe diarrhea for more than 6 hours.

Additional emergency warning signs include:

  • Chest pain or pressure
  • Severe abdominal pain
  • Confusion or inability to think clearly
  • Slurred speech
  • Loss of consciousness
  • Seizures
  • Fruity-smelling breath (a sign of ketoacidosis)
  • Rapid, deep breathing

Minor illnesses in people with diabetes (especially children with type 1 diabetes) can lead to very high blood sugar levels and possible emergencies. When children are sick, watch them closely for signs that they need medical attention right away.

Building Your Diabetes Sick Day Kit

If you do get sick, it’ll make things easier if you already have a sick-day kit ready to go with the things you’ll need. You might want to include: A week’s worth of glucose-lowering medication (don’t store these longer than 30 days before use). Having supplies ready before you need them eliminates the stress of trying to gather items when you’re feeling unwell.

Essential Supplies for Your Sick Day Kit

Your diabetes sick day kit should include:

  • Blood glucose meter with extra test strips and batteries
  • Urine ketone test strips in your home that are not expired
  • Thermometer
  • Extra diabetes medications and insulin
  • Glucose tablets or gel for treating low blood sugar
  • Fast-acting carbohydrate sources (regular soda, juice, honey)
  • Easy-to-digest foods (crackers, applesauce, broth, gelatin)
  • Sugar-free beverages
  • Anti-nausea medication (as approved by your doctor)
  • Anti-diarrheal medication
  • Pain reliever/fever reducer (acetaminophen or as recommended)
  • Antacid
  • Written sick day plan
  • Emergency contact numbers
  • Current medication list
  • Insurance information

Keep sugar-free liquids and liquids with 15 grams of carbohydrates in your home. Having both options available ensures you can respond appropriately whether your blood sugar is high or low.

Stock your sick day kit with foods that are easy to consume when you’re not feeling well. Each of the following contains approximately 15 grams of carbohydrates:

  • 1/2 cup regular soft drink (caffeine-free)
  • 1/2 cup fruit juice
  • 1 cup sports drink
  • 1 double-stick popsicle
  • 1/4 cup regular pudding
  • 1/2 cup regular gelatin
  • 6 saltine crackers
  • 1 slice dry toast
  • 1/2 cup cooked cereal
  • 1 1/2 cups unsweetened applesauce

For hydration when blood sugar is elevated, keep sugar-free options like:

  • Water
  • Sugar-free gelatin
  • Diet soda
  • Sugar-free sports drinks
  • Broth or bouillon
  • Herbal tea

Monitoring and Record-Keeping During Illness

Detailed record-keeping becomes even more important when you’re sick. Your records help you and your healthcare team make informed decisions about your care and can reveal patterns that might otherwise go unnoticed.

What to Track

During illness, keep a detailed log that includes:

  • Date and time of each blood sugar reading
  • Blood sugar levels
  • Ketone test results (if applicable)
  • All medications taken, including doses and times
  • Food and beverage intake, including estimated carbohydrates
  • Symptoms experienced
  • Temperature readings
  • Fluid intake
  • Any vomiting or diarrhea episodes
  • Activity level
  • Weight (daily)

Weigh yourself every day. Losing weight without trying is a sign of high blood sugar. Check your temperature every morning and evening. A fever may be a sign of infection.

Special Considerations for Different Types of Diabetes

Type 1 Diabetes Sick Day Management

People with Type 1 diabetes face unique challenges during illness because their bodies produce no insulin. During sick days most people (adults and children) with diabetes may require more insulin. The stress hormones released during illness increase insulin resistance, meaning you may need to increase your insulin doses even if you’re eating less than usual.

If you have type 1 diabetes check your urine for ketones when your blood sugar is 300 or higher. Call you 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.

Never stop taking insulin, even if you can’t eat. Your body needs basal insulin to function, and during illness, you may need supplemental doses to correct high blood sugar and ketones.

Type 2 Diabetes Sick Day Management

People with Type 2 diabetes also need to be vigilant during illness, though the management approach may differ slightly. If you don’t take insulin, continue to take your diabetes medications, even if you are sick and have been throwing up.

However, certain medications require special attention during illness. If a person with T2D takes metformin tablets, it may be necessary to temporarily stop these tablets. This is usually advised if the person has a severe infection or becomes dehydrated. If it is necessary to stop taking metformin, then an alternative treatment needs to be put in place until the metformin treatment can be resumed.

Always consult with your healthcare provider about medication adjustments during illness, as individual circumstances vary.

Preventive Measures to Reduce Illness Risk

While you can’t prevent all illnesses, taking proactive steps can significantly reduce your risk and help you stay healthier throughout the year.

Vaccinations

You’ll also want to be sure to get your annual flu shot to make getting the flu less likely. People with diabetes are more vulnerable to complications from influenza, and infections can trigger the release of stress hormones that raise blood sugar. Follow up with your physician about annual flu vaccinations, as well as RSV and pneumonia vaccines, and remember to practice good hand hygiene.

Recommended vaccinations for people with diabetes include:

  • Annual influenza vaccine
  • Pneumococcal vaccines (as recommended by age and risk factors)
  • COVID-19 vaccines and boosters
  • RSV vaccine (for eligible individuals)
  • Tdap (tetanus, diphtheria, pertussis) booster
  • Hepatitis B vaccine
  • Shingles vaccine (for those 50 and older)

Hygiene and Infection Prevention

Getting your flu jab every year and avoiding people who are sick and washing your hands often and thoroughly can help to protect yourself and others too. Simple hygiene practices can dramatically reduce your exposure to infectious diseases.

Key infection prevention strategies include:

  • Washing hands frequently with soap and water for at least 20 seconds
  • Using alcohol-based hand sanitizer when soap isn’t available
  • Avoiding touching your face, especially eyes, nose, and mouth
  • Staying away from people who are sick
  • Avoiding crowded places during peak illness seasons
  • Cleaning and disinfecting frequently touched surfaces
  • Practicing good respiratory hygiene (covering coughs and sneezes)
  • Staying home when you’re sick to avoid spreading illness

Maintaining Overall Health

Your overall health status significantly impacts your ability to fight off infections and recover from illness. Focus on:

  • Blood sugar control: Maintaining good blood sugar control reduces your risk of infections and complications
  • Adequate sleep: Getting 7-9 hours of quality sleep supports immune function
  • Balanced nutrition: Eating a variety of nutrient-rich foods strengthens your immune system
  • Regular physical activity: Exercise boosts immune function and overall health
  • Stress management: Chronic stress weakens immunity and affects blood sugar control
  • Proper hydration: Staying well-hydrated supports all body systems
  • Regular medical care: Keeping up with routine check-ups and screenings

Understanding Stress Hyperglycemia

Illness or stress can trigger hyperglycemia. That’s because hormones your body makes to fight illness or stress can also cause blood sugar to rise. You may need to take extra diabetes medication to keep blood glucose in your target range during illness or stress.

The hormones involved in the stress response include:

  • Cortisol: Often called the “stress hormone,” cortisol increases glucose production in the liver
  • Epinephrine (adrenaline): Triggers the release of stored glucose and reduces insulin effectiveness
  • Glucagon: Signals the liver to release stored glucose into the bloodstream
  • Growth hormone: Reduces insulin sensitivity and increases glucose production

These hormones work together to ensure your body has enough energy to fight infection or deal with stress, but they create challenges for diabetes management.

Communication with Your Healthcare Team

Effective communication with your healthcare providers is essential for successful sick day management. Don’t hesitate to reach out when you need guidance or support.

When to Contact Your Healthcare Provider

Contact your healthcare provider if:

  • You’ve been sick for more than 24 hours without improvement
  • You’re unable to keep food or fluids down for more than 6 hours
  • You have moderate to large ketones in your urine or blood
  • Your blood sugar remains above 240 mg/dL despite taking extra insulin or medication
  • Your blood sugar drops below 70 mg/dL repeatedly
  • You have a fever above 101°F (38.3°C) for more than 24 hours
  • You’re experiencing symptoms of dehydration
  • You’re unsure about how to adjust your medications
  • You have questions about your sick day plan
  • Your symptoms are worsening or not improving

Information to Have Ready

When contacting your healthcare provider, have the following information available:

  • Recent blood sugar readings (at least the past 24 hours)
  • Ketone test results
  • Current symptoms and their duration
  • Temperature readings
  • Medications taken, including doses and times
  • Food and fluid intake
  • Any other relevant medical information

Special Situations and Considerations

Surgery and Medical Procedures

A sick day can be caused by a cold, flu, surgery, infection, injury, stress or dental work. Planned medical procedures require advance planning with your healthcare team. Your diabetes management plan may need significant adjustments before, during, and after procedures.

Before any surgery or procedure:

  • Inform all healthcare providers that you have diabetes
  • Discuss medication adjustments well in advance
  • Understand fasting requirements and how they affect your diabetes management
  • Plan for blood sugar monitoring during and after the procedure
  • Know what to expect regarding blood sugar fluctuations during recovery

Steroid Medications

If you have diabetes, taking high doses of steroids for periods of time can make your blood sugar levels rise. This is called steroid-induced hyperglycaemia. Your doctor or nurse will talk to you about this. They may ask you to make some changes to how you manage your diabetes, so that you can keep your blood sugar levels within your target range.

If you’re prescribed steroids for any reason, work closely with your healthcare team to adjust your diabetes management plan accordingly. You may need increased monitoring and medication adjustments throughout the course of steroid treatment.

Over-the-Counter Medications

Be careful with over-the-counter medicines. Don’t take any nonprescription medicines unless you talk to your doctor first. Many nonprescription medicines can affect your blood sugar level.

Some over-the-counter medications to be cautious with include:

  • Decongestants containing pseudoephedrine or phenylephrine
  • Cough syrups with sugar or alcohol
  • Pain relievers (some may interact with diabetes medications)
  • Certain herbal supplements
  • Medications containing caffeine

Always read labels carefully and consult with your pharmacist or healthcare provider before taking any new medication, even if it’s available without a prescription.

Recovery and Returning to Normal Management

As you recover from illness, gradually transition back to your normal diabetes management routine. Continue monitoring your blood sugar more frequently until it stabilizes at your usual levels. It may take several days after you feel better for your blood sugar patterns to return to normal.

During recovery:

  • Continue frequent blood sugar monitoring until levels stabilize
  • Gradually return to your normal eating pattern
  • Resume regular physical activity slowly
  • Continue taking medications as prescribed
  • Stay well-hydrated
  • Get adequate rest
  • Follow up with your healthcare provider as recommended

Learning from Each Illness Experience

Each time you manage diabetes through an illness, you gain valuable experience. After recovering, take time to review what worked well and what could be improved. Consider:

  • Were you adequately prepared with supplies?
  • Did you contact your healthcare provider at the right time?
  • Were your medication adjustments effective?
  • Did you maintain adequate hydration and nutrition?
  • What would you do differently next time?
  • Do you need to update your sick day plan?

Use these insights to refine your sick day plan and improve your preparedness for future illnesses.

Essential Reminders for Diabetes Sick Day Management

  • Never stop taking insulin or diabetes medications without consulting your healthcare provider, even if you can’t eat normally
  • Monitor blood sugar every 2-4 hours during illness, or more frequently if needed
  • Test for ketones when blood sugar is elevated, especially if you have Type 1 diabetes
  • Stay hydrated by drinking fluids throughout the day, aiming for at least 8-12 cups daily
  • Keep detailed records of blood sugar levels, medications, food intake, and symptoms
  • Have a sick day plan prepared in advance and keep it easily accessible
  • Maintain a well-stocked sick day kit with all necessary supplies and medications
  • Know when to seek emergency care and don’t hesitate to get help when needed
  • Communicate with your healthcare team early and often during illness
  • Get recommended vaccinations to reduce your risk of preventable illnesses
  • Practice good hygiene and infection prevention strategies year-round
  • Inform family members about your sick day plan and warning signs to watch for

Additional Resources and Support

Managing diabetes during illness can feel overwhelming, but you don’t have to do it alone. Numerous resources are available to support you:

  • American Diabetes Association: Offers comprehensive information, support groups, and educational materials at diabetes.org
  • Centers for Disease Control and Prevention: Provides evidence-based guidance on diabetes management at cdc.gov/diabetes
  • Diabetes educators: Certified diabetes care and education specialists can provide personalized guidance
  • Support groups: Connect with others managing diabetes for shared experiences and advice
  • Telehealth services: Many healthcare providers offer virtual consultations for sick day management

Remember that managing diabetes during illness is a learned skill that improves with experience. By preparing in advance, staying vigilant, and working closely with your healthcare team, you can successfully navigate sick days while minimizing complications and maintaining your health. Your proactive approach to sick day management is an investment in your long-term wellbeing and quality of life.