Illness can push blood glucose higher or lower, complicating routine care. Managing sick days with diabetes takes planning, frequent checks, and clear action steps. This guide summarizes monitoring, ketones, fluids, nutrition, and when to escalate care, drawing on established clinical guidance and practical strategies.
Key Takeaways
- Monitor frequently: glucose and ketones rise quickly during illness.
- Hydrate steadily: use electrolyte fluids and slow sips.
- Continue background insulin unless told otherwise by a clinician.
- Use a written plan: meds to hold, carb targets, phone numbers.
- Escalate early for sustained high glucose, ketones, or dehydration.
Why Illness Disrupts Glucose Control
During infections or fever, stress hormones like cortisol and catecholamines increase hepatic glucose output. That response can drive insulin resistance and unpredictable swings in glucose. Vomiting, poor appetite, and diarrhea can also reduce carbohydrate intake, leading to hypoglycemia if doses are not matched. Recognizing these opposing forces helps you plan for more frequent checks and careful adjustments supervised by your clinician.
Respiratory viruses, gastrointestinal bugs, and urinary infections are common triggers. People managing type 2 diabetes and viral infections often see higher readings for several days. Immune activation, dehydration, and altered medication absorption compound the issue. Authoritative organizations outline core principles for ill-day care; see ADA sick day advice for practical guardrails (ADA sick day advice). For seasonal infections, review CDC flu guidance to reduce exposure and complications (CDC flu guidance).
Sick Days With Diabetes: Core Actions
Start with a written plan. Include monitoring frequency, thresholds for ketone checks, sick-day carbohydrate targets, medication adjustments preapproved by your clinician, and emergency contacts. Keep supplies on hand: meter, strips, lancets, ketone strips (urine or blood), glucagon as prescribed, thermometer, electrolyte drinks, and simple carbohydrates. For meter supplies and compatibility, see Contour Next Test Strips for an overview of strip options (Contour Next Test Strips).
Check glucose every 3–4 hours, or per your provider’s guidance. Increase to every 2 hours if levels trend upward, if you have fever, or if you use rapid-acting insulin with correction doses. Check ketones when glucose is high, when nauseated, or if you feel unwell. Continue basal insulin unless your clinician has advised otherwise, because it helps prevent ketosis. For detailed monitoring cadence, see Monitoring Frequency Guide, which reviews timing and patterns during routine and illness (Monitoring Frequency Guide).
When to Test for Ketones and Adjust Care
Ketonemia can develop during dehydration, insulin deficit, or prolonged fasting. Test if glucose is persistently elevated, if you have fever, or when vomiting. Home blood ketone meters detect beta-hydroxybutyrate, while urine strips detect acetoacetate. Rising ketones suggest insulin deficit and dehydration risk. Follow your plan for fluids, carbohydrates, and supplemental insulin as directed by your clinician. For threshold ranges and stepwise actions, see Ketones in Diabetes for practical interpretation details (Ketones in Diabetes).
Written protocols often emphasize specific ketone levels and correction strategies. Including “red line” values helps decision-making when you feel unwell. Guidance also covers diabetes sick day rules ketones, which prioritize hydration and timely assessment. If ketones do not normalize with your plan, contact your care team or seek urgent care. Early escalation prevents complications and shortens recovery.
Medications, Hydration, and Nutrition During Illness
Hydration matters. Aim for steady sips of water or oral rehydration solutions, especially if you are febrile or have diarrhea. When solid food is difficult, use carbohydrate-containing liquids (broth, diluted juice, or oral rehydration) to match your insulin. Read labels for carbohydrate content and sodium. For label tactics during illness, see Food Labels With Diabetes to choose appropriate options (Food Labels With Diabetes).
Over-the-counter choices require care. Many cough and cold remedies contain sugars or decongestants that may raise glucose. Select products without added sugars and avoid multi-symptom combinations if unnecessary. Discuss antipyretic (fever-reducer) use, decongestants, and antihistamines with your clinician or pharmacist. When considering the best cold medicine for diabetes, prioritize single-ingredient formulations and monitor glucose closely after dosing.
Note: Some medications (e.g., NSAIDs) interact with blood pressure or kidney drugs. Confirm combinations with a clinician. If nausea is severe, your clinician may discuss antiemetics. For an overview of an option sometimes used for nausea, see Metoclopramide for indications and cautions in adults (Metoclopramide).
Nutrition should be simple and tolerable: toast, rice, applesauce, bananas, soups, or yogurt. Vitamin-rich foods like berries may support overall nutrition during recovery; see Berries and Diabetes for balanced snack ideas and glycemic impact (Berries and Diabetes).
Type 1 vs. Type 2 Considerations
People with type 1 have absolute insulin deficiency risk and need vigilant ketone checks during illness. Even with lower carbohydrate intake, they usually need background insulin to prevent ketosis. Parents and caregivers should know correction plans, basal adjustments approved by clinicians, and indicators for urgent evaluation. Pediatric care teams often follow structured protocols, informed by international pediatric diabetes guidance. For detailed frameworks, see the ISPAD consensus statement on acute illness care (ISPAD consensus statement).
People with type 2 also face hyperglycemia during infection, especially with dehydration or steroid use. Medication holds or dose changes should be clinician-directed, particularly for agents affected by renal function or dehydration risk. Plans often reference sick day rules diabetes type 2, including when to pause metformin during vomiting or dehydration, and when to reintroduce it. If you use insulin, discuss preapproved correction scales and thresholds for ketone checks even in type 2.
Nausea, Vomiting, and Dehydration
Frequent vomiting increases dehydration and hypoglycemia risk, even when glucose appears high. Use small, repeated sips of oral rehydration solution, broth, or diluted juice to maintain fluids and some carbohydrates. If you cannot keep fluids down for four hours, contact your care team. For people seeking what to do when a diabetic is vomiting, the priorities are hydration, ketone checks, and clinician-guided insulin use to prevent ketosis.
Nausea may be stronger in the morning or after meals. Adjust your meal texture and portion size to improve tolerance. Clear soups and soft foods may help prevent spikes and crashes. Persistent vomiting, abdominal pain, or rapid breathing can signal ketosis risk and need prompt evaluation. For balanced snack ideas during recovery days, see Healthy Snacking Guide to maintain energy with stable glucose (Healthy Snacking Guide).
Preventing Infections and Building a Plan
Vaccination reduces complications from influenza and pneumonia, both of which stress glucose control. Hand hygiene, mask use during peak seasons, and avoiding close contact with sick individuals also help. Workplaces and schools increase exposure, so plan ahead for healthier routines and access to supplies. For respiratory seasons, the CDC outlines strategies to protect high-risk groups, including people with diabetes (CDC seasonal guidance).
Write your sick-day plan with your clinician and keep copies at home and work. The plan should reference ada sick day guidelines, personal thresholds for glucose and ketones, and specific phone numbers. Include which medications to hold during dehydration, what fluids to choose, and when to seek urgent care. For broader learning tools and planning checklists, see Education Week Tools for links to evidence-based resources and worksheets (Education Week Tools).
When to Seek Urgent Care
Escalate care early if you cannot keep fluids down, have moderate to high ketones that do not resolve, or experience persistent fever. Seek urgent evaluation for confusion, chest pain, trouble breathing, severe abdominal pain, or signs of dehydration like fainting or minimal urine. Emergency teams can provide fluids, electrolytes, and guided insulin therapy as needed. Clinical teams also rule out secondary issues like pneumonia or urinary infection.
Be particularly cautious with dka in type 2 diabetes, which can occur during severe illness, dehydration, or insulin deficiency. People using SGLT2 inhibitors may rarely develop euglycemic ketosis, which presents with normal or mildly elevated glucose. If you are unsure whether to adjust insulin or hold oral agents, contact your clinician promptly. For context on sick-day risks and glucose patterns at work, see Diabetes at Work for practical planning ideas during busy seasons (Diabetes at Work).
Recap
Illness complicates diabetes care, but planning and early action reduce risk. Monitor more often, check ketones when indicated, maintain hydration, and follow a clinician-approved plan. Use single-ingredient OTCs carefully, keep a supply kit, and escalate early for red flags. For additional reading across nutrition, monitoring, and prevention, browse the Diabetes articles library to build a personalized toolkit (Diabetes).
Tip: Keep a sealed “sick-day kit” with strips, ketone tests, oral rehydration, easy carbs, thermometer, and your written plan. Replace items before they expire.
This content is for informational purposes only and is not a substitute for professional medical advice.


