Written by Dr. Matthew Capozzi, DPM, FACFAS, CWS (board-certified foot surgeon and wound specialist) · Medically reviewed by the CircuFiber Scientific Advisory Board · Updated: October 27, 2026

A diabetic emergency is a sudden, dangerous swing in blood sugar: either hypoglycemia (blood sugar below 70 mg/dL) or severe hyperglycemia that progresses to diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemic state (HHS). Hypoglycemia is treated on the spot with fast-acting carbohydrates such as glucose tablets or juice, while DKA and HHS need emergency medical care because they require intravenous fluids, electrolytes and insulin. Most diabetic emergencies can be prevented with regular blood sugar monitoring, taking medication as prescribed, and a steady routine of balanced meals and physical activity.

Key Takeaways

• The three main diabetic emergencies are hypoglycemia (low blood sugar), diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic state (HHS, also called HHNS).
• Hypoglycemia means blood sugar below 70 mg/dL. Immediate action is to eat or drink fast-acting carbohydrates such as glucose tablets, fruit juice, regular soda or candy, then recheck and follow with a snack.
• DKA and HHS are high blood sugar emergencies. DKA usually involves blood sugar over 250 mg/dL with ketones and develops within about 24 hours; HHS involves blood sugar over 600 mg/dL and develops over days to weeks. Both need emergency medical care.
• Call emergency services if someone with diabetes is confused, cannot safely swallow, has a seizure, or is unconscious. Never give food or drink to someone who cannot swallow.
• Prevention comes down to regular blood sugar monitoring, adherence to prescribed medication, a balanced high-fiber diet, regular exercise, extra care during illness, and a written action plan agreed with your healthcare team.
• Chronic complications such as diabetic neuropathy, retinopathy, nephropathy and cardiovascular disease also need ongoing management, because they can turn into emergencies of their own.

What is a diabetic emergency?

A diabetic emergency is a critical situation caused by blood sugar that is dangerously low or dangerously high, and it demands immediate attention. We often hear about the long-term effects of diabetes, but it's the sudden, unexpected emergencies that can catch us off guard. These critical situations require immediate attention and knowing how to respond can make all the difference.

From hypoglycemia to diabetic ketoacidosis, the range of diabetic emergencies varies widely, each with its own set of signs and challenges. Recognizing these emergencies early can be a game-changer in ensuring health safety. Being informed is the first step towards ensuring safety for ourselves or our loved ones living with diabetes.

Hypoglycemia (low blood sugar)

Hypoglycemia occurs when blood sugar levels drop below 70 mg/dL. Symptoms often include dizziness, confusion, sweating, and in severe cases, loss of consciousness. Factors leading to this condition entail skipped meals, excessive insulin administration, or unplanned physical activity. Our guide to recognizing hypoglycemia and its quick fixes covers the early signs in more detail.

Diabetic ketoacidosis (DKA)

Diabetic ketoacidosis (DKA) manifests due to exceedingly high blood sugar levels, generally over 250 mg/dL, accompanied by ketone buildup in the blood. Symptoms span from extreme thirst, frequent urination, nausea, to deep and rapid breathing. It more commonly affects individuals with type 1 diabetes but can also occur in type 2 diabetes under certain conditions like infection or illness. Read more about diabetic ketoacidosis symptoms and treatment.

Hyperosmolar hyperglycemic state (HHS or HHNS)

The hyperosmolar hyperglycemic state (HHS), also called hyperosmolar hyperglycemic nonketotic syndrome (HHNS), is a severe complication primarily seen in individuals with type 2 diabetes, characterized by blood sugar levels exceeding 600 mg/dL without significant ketone presence. Symptoms mirror those of DKA but may also involve confusion, hallucinations, or coma.

What are the signs of a diabetic emergency?

The signs of a diabetic emergency depend on whether blood sugar is too low or too high, and the first action is different for each. The table below summarizes the warning signs of hypoglycemia, diabetic ketoacidosis and hyperosmolar hyperglycemic state and what to do for each one.

For a side-by-side look at how high and low blood sugar episodes feel, see our article on hyperglycemia and hypoglycemia attack symptoms.

What should you do in a diabetic emergency?

In a diabetic emergency, check blood sugar if you can, treat low blood sugar immediately with fast-acting carbohydrates, and call for emergency medical help for suspected DKA or HHS or for anyone who is confused, unable to swallow, or unconscious. In each of these conditions, proactivity and quick response are pivotal. Keeping emergency contacts handy and discussing a clear action plan with healthcare providers ensure preparedness.

How to treat hypoglycemia

Immediate treatment for hypoglycemia hinges on raising blood sugar levels quickly. Consuming fast-acting carbohydrates is a pivotal first step. Examples include glucose tablets, fruit juice, regular—not diet—soda, or candy. It's crucial for patients and their caregivers to keep such remedies readily accessible. Continuous monitoring post-intervention helps prevent recurrence and ensures stability.

Following the initial management with fast-acting sugars, it's advisable to consume a more substantial snack or meal that includes complex carbohydrates and protein to stabilize blood sugar levels further. This ensures a more lasting resolution to the immediate crisis. In the event symptoms don't improve after taking fast-acting carbohydrates, or if the individual is unable to ingest these on their own due to confusion or unconsciousness, seeking emergency medical assistance becomes necessary. In such scenarios, medical professionals may administer intravenous glucose or injectable glucagon to restore normal blood sugar levels.

The causes of hypoglycemia in individuals with diabetes are varied, encompassing factors like insufficient food intake, excessive physical exertion without adequate carbohydrate consumption, or an imbalance in medication dosage, particularly with insulin. It's imperative for patients to understand these triggers to mitigate their risk. Learn the ranges that count as low in our guide to recognizing low blood sugar levels.

How to respond to hyperglycemia before it becomes DKA

Hyperglycemia, or high blood sugar, emerges when the body has too little insulin or when it cannot efficiently use the insulin it has. Several factors can trigger hyperglycemia, including insufficient insulin dosages, overconsumption of carbohydrates, stress, or a lack of physical activity. Common symptoms include frequent urination, increased thirst, blurred vision, fatigue, and in some cases, an unexplained weight loss.

Immediate interventions involve adjusting insulin doses as per medical guidance, increasing fluid intake to prevent dehydration, and closely monitoring blood sugar levels. It's essential to consult healthcare providers when adjustments in self-care practices do not effectively lower blood sugar levels.

How diabetic ketoacidosis is treated

Diabetic ketoacidosis results from a shortage of insulin in the body, leading to high blood sugar levels and the production of ketones, acidic substances formed when the body breaks down fats for energy. The combination of high blood sugar and high ketone levels turns the blood acidic, which can be life-threatening if not treated promptly. Symptoms of DKA can develop quickly, often within 24 hours, making early detection and treatment vital. Treatment typically involves insulin administration, fluid replacement, and electrolyte management, usually in a hospital setting to closely monitor the patient's response to treatment. Early detection through regular monitoring of blood sugar and ketone levels can prevent the progression of this emergency.

How hyperosmolar hyperglycemic state is treated

HHS typically develops over days to weeks, marked by extremely high blood sugar levels that can exceed 600 mg/dL. Such drastic increases in blood sugar cause the body to try to rid itself of the excess glucose through increased urination, which can lead to severe dehydration if not managed promptly. Several factors can trigger HHS, including infections, illnesses, medications that increase blood sugar, and inadequate fluid intake.

Immediate medical intervention is crucial upon noticing signs of HHS. Before reaching a medical facility, increasing fluid intake (if possible) and checking blood sugar levels frequently can help manage the situation. Management of HHS requires hospital admission where healthcare professionals administer fluids, electrolytes, and insulin to gradually lower blood sugar levels safely.

Which chronic complications of diabetes can turn into emergencies?

Diabetic neuropathy, diabetic retinopathy, diabetic nephropathy and cardiovascular disease are the chronic complications most likely to produce an emergency if they are not managed. Chronic complications, if not managed efficiently, can severely impact an individual's quality of life, so they belong in the same prevention plan as blood sugar emergencies.

Diabetic neuropathy and foot infections

Diabetic neuropathy stands out as a prevalent chronic complication. It involves nerve damage resulting from prolonged high blood sugar levels. Individuals may experience symptoms like tingling, numbness, or pain, predominantly in their feet and legs. Regular foot inspections are essential to prevent infections, given the reduced sensation in these areas. Incorporating specific exercises and maintaining optimal blood sugar levels can mitigate the symptoms significantly. See our overview of diabetic neuropathy types and management and what to do about a diabetic foot infection, which can itself become an emergency.

Diabetic retinopathy

Diabetic retinopathy is a condition affecting the eyes. It's the direct result of damage to the blood vessels in the retina due to high blood sugar. Its early detection through annual eye exams can prevent severe vision loss. Managing blood sugar, blood pressure, and cholesterol levels can slow down its progression. Read more on diabetic retinopathy causes and treatment.

Diabetic nephropathy (kidney disease)

Diabetic nephropathy, a form of kidney disease, can progress to kidney failure if left unattended. Monitoring kidney function regularly through specific tests, managing blood sugar and blood pressure, and making dietary adjustments form the cornerstone of preventing its progression.

Heart attack and stroke

Diabetes significantly increases the risk of cardiovascular diseases, including heart attack and stroke. Adopting a heart-healthy lifestyle, which includes a balanced diet, physical activity, and tobacco cessation, plays a pivotal role in managing this risk. Our article on diabetes and stroke risk explains the warning signs to know.

How can you prevent diabetic emergencies?

Diabetic emergencies are prevented by keeping blood sugar in your target range through regular monitoring, medication adherence, a balanced diet, regular exercise and a plan for sick days. Consistent management of diabetes through regular monitoring, medication adherence, and lifestyle adjustments minimizes the risk of encountering such emergencies.

Monitor blood sugar and take medication as prescribed

Regular monitoring of blood sugar levels and adherence to prescribed medication are the foundation of prevention. It's vital to regularly monitor blood glucose levels before and after meals and physical activity to understand the body's response and adjust food intake and exercise accordingly. Preventing HHS in particular involves meticulously managing blood sugar levels, especially during sickness or stress, and ensuring adequate hydration. If you are new to testing, start with our tips for blood sugar monitoring and why checking your blood sugar matters.

Eat a balanced, high-fiber diet

A balanced diet is the cornerstone of diabetes management. It helps in controlling blood sugar levels, keeping them within the target range to avert the risk of both hypoglycemia and hyperglycemia. Eating a variety of foods rich in fiber, such as fruits, vegetables, and whole grains, aids in the gradual release of glucose into the bloodstream, ensuring steady blood sugar levels. Incorporating lean proteins and healthy fats also contributes to satiety and better blood sugar control. Monitoring carbohydrate intake, through methods such as carb counting or using the glycemic index, enables individuals to understand how different foods affect their glucose levels, thereby avoiding spikes that could trigger diabetic emergencies.

Exercise regularly, with your doctor's guidance

Exercise enhances the body's sensitivity to insulin, making it more efficient at converting glucose into energy. Regular physical activity, hence, not only lowers blood sugar levels but also decreases the need for insulin or oral diabetes medications. Aerobic exercises, such as brisk walking, swimming, or cycling, are especially beneficial as they help in weight management, a critical factor in controlling diabetes. Strength training, at least twice a week, also plays a crucial role by increasing muscle mass, which in turn boosts metabolism and improves glucose management. It's essential for individuals with diabetes to consult with their healthcare provider before starting any new exercise regimen, especially if they have existing complications. This step ensures that the chosen activities are safe and align with their overall health goals. For a practical starting point, read managing diabetes with exercise and diet.

Build the habits into everyday life

Adopting these dietary and exercise recommendations requires making thoughtful choices daily. Planning meals ahead, keeping healthy snacks on hand, and scheduling regular physical activities can help integrate these practices into one's routine. Support from healthcare professionals, including dietitians and diabetes educators, can provide personalized guidance to navigate these lifestyle adjustments effectively. Regular check-ups with healthcare providers, proactive management of blood sugar, and lifestyle changes are indispensable for preventing diabetic emergencies and managing chronic complications.

When should you see a doctor about a diabetic emergency?

Call emergency services right away if a person with diabetes is confused, unable to swallow safely, having a seizure, breathing deeply and rapidly, or unconscious, or if low blood sugar does not improve after fast-acting carbohydrates. Seek urgent medical care for suspected diabetic ketoacidosis (blood sugar over 250 mg/dL with ketones, vomiting, abdominal pain or fruity breath) or hyperosmolar hyperglycemic state (blood sugar over 600 mg/dL with severe thirst, weakness or confusion). Outside of an emergency, contact your healthcare provider if you have repeated low blood sugar episodes, if high readings do not come down with your usual self-care, or if you are sick and cannot keep fluids down. Emphasizing the need for early recognition and intervention alongside regular monitoring and lifestyle adjustments offers a roadmap to better health, and consulting healthcare providers is key to tailoring these practices to meet personal health needs safely.

Frequently asked questions about diabetic emergencies

What are the 5 signs of a diabetic emergency?

Five signs that a person with diabetes needs immediate help are confusion or unusual behavior, heavy sweating with shakiness, extreme thirst with frequent urination, nausea or vomiting with fruity-smelling breath, and drowsiness or loss of consciousness. The first two usually point to low blood sugar; the next two point to very high blood sugar and possible ketoacidosis; the last can happen with either and always needs emergency care.

What is the best sugar or candy for a diabetic emergency?

The best choice for a low blood sugar emergency is a fast-acting carbohydrate that contains little fat or protein, such as glucose tablets or gel, half a cup of fruit juice, regular (not diet) soda, or hard candy. Chocolate is a poor choice because its fat slows sugar absorption. After blood sugar comes back up, eat a snack with complex carbohydrates and protein to keep it stable.

What should be in a diabetic emergency kit?

A diabetic emergency kit should contain a fast-acting sugar source (glucose tablets, juice boxes or candy), a blood glucose meter with strips and lancets, ketone test strips if you use insulin, any glucagon your doctor has prescribed, a list of your medications and doses, and emergency contact numbers. Keep one at home, one at work or school, and one in your bag, and check expiration dates regularly.

What is the diabetic emergency shot?

The diabetic emergency shot is glucagon, a hormone that tells the liver to release stored sugar into the bloodstream. It is used when a person with severe hypoglycemia is unconscious or cannot swallow safely. Medical professionals may administer injectable glucagon or intravenous glucose; glucagon is also available by prescription for family members or caregivers to use, so ask your doctor whether you should keep it on hand.

What is the difference between DKA and HHS?

Diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic state (HHS) are both high blood sugar emergencies, but DKA involves ketones that make the blood acidic, develops within about 24 hours, and is more common in type 1 diabetes, while HHS involves much higher blood sugar (over 600 mg/dL) without significant ketones, develops over days to weeks, and is seen mainly in type 2 diabetes. Both require hospital treatment with fluids, electrolytes and insulin.

Can you have a diabetic emergency without knowing you have diabetes?

Yes. Diabetic ketoacidosis is sometimes the first sign of undiagnosed type 1 diabetes, and HHS can occur in older adults whose type 2 diabetes was never diagnosed. Extreme thirst, frequent urination, unexplained weight loss, vomiting and confusion in someone without a diagnosis are reasons to seek urgent medical care. Our guide to the early signs and symptoms of diabetes lists the warning signs to watch for.

References, studies and sources

• American Red Cross. Diabetic Emergencies: First Aid Steps. https://www.redcross.org/take-a-class/resources/learn-first-aid/diabetic-emergencies
• American Diabetes Association. Diabetes and complications resources. https://diabetes.org/
• Centers for Disease Control and Prevention. Diabetes. https://www.cdc.gov/diabetes/
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Diabetes. https://www.niddk.nih.gov/health-information/diabetes
• Mayo Clinic. Diabetes: Symptoms and causes. https://www.mayoclinic.org/diseases-conditions/diabetes/symptoms-causes/syc-20371444

About the author: Dr. Matthew Capozzi, DPM, FACFAS, CWS, is a board-certified foot surgeon through the American Board of Foot and Ankle Surgery. He is a Diplomate of the American Academy of Wound Management and Fellow of the American College of Foot and Ankle Surgeons. He completed a three-year residency program in Foot and Ankle Reconstructive Surgery at St. Francis Hospital & Medical Center in Hartford, CT in 2010. Dr. Capozzi is a board-certified Wound Specialist® granted by the American Academy of Wound Management.

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