Diabetic ketoacidosis is a serious and potentially life-threatening emergency that can affect people with diabetes when their bodies run dangerously low on insulin, leading to a toxic buildup of acids in the blood.

What is Diabetic Ketoacidosis?

Diabetic ketoacidosis, often called DKA, represents one of the most dangerous complications that can arise from diabetes. This condition occurs when your body doesn’t have enough of a hormone called insulin, which normally helps sugar from your blood enter your cells to be used as energy. Without sufficient insulin, your body cannot use sugar properly, so it begins to break down fat for fuel instead. When fat breaks down, it produces acidic substances called ketones. If these ketones accumulate too quickly in your blood, they make your blood become acidic, creating a dangerous situation that requires immediate medical attention.^[1]

The body’s normal process of using sugar for energy becomes disrupted during DKA. As your liver processes fat into ketones to use as an alternative fuel source, these ketones build up faster than your body can eliminate them. This accumulation turns your blood acidic, which disrupts the normal chemical balance your body needs to function. The condition also causes significant fluid loss through frequent urination, leading to severe dehydration. All of these changes happening together create a medical emergency that, without proper treatment, can lead to coma or death.^[3]

Epidemiology

Diabetic ketoacidosis occurs most commonly in people with type 1 diabetes, though it can also affect those with type 2 diabetes. The condition is more frequent than many people realize, and it represents a major cause of hospital admissions among people with diabetes worldwide.^[2]

For some people, DKA is actually the first sign that they have diabetes. Studies show that approximately 20% to 40% of people who experience DKA are learning for the first time that they have type 1 diabetes. This is particularly common in children and adolescents who develop diabetes suddenly and have not yet been diagnosed. However, DKA can occur at any point in someone’s life with diabetes if they don’t receive adequate insulin.^[7]

The rates of DKA vary significantly around the world. While some developed countries have seen improvements in prevention and management, other regions continue to experience high rates of this complication. In certain areas, DKA rates among newly diagnosed type 1 diabetes patients can range from less than 20% to as high as 80%, depending on access to healthcare and diabetes awareness. Despite medical advances, the mortality rate from DKA has remained relatively steady at 1 to 2 percent since the 1970s, emphasizing that this remains a serious health concern.^[4]

Causes

The fundamental cause of diabetic ketoacidosis is an absolute or relative lack of insulin in the body. Very high blood sugar levels combined with low insulin levels create the conditions for DKA to develop. When insulin is insufficient or absent, sugar cannot enter cells for energy, so the body turns to breaking down fat. This fat breakdown produces ketones at a rate faster than the body can process them safely.^[2]

The two most common triggers for DKA are illness and problems with insulin administration. When you become sick with an infection, injury, or other acute medical condition, your body’s stress response can interfere with blood sugar control and increase insulin needs. At the same time, you may not be able to eat or drink normally, making it harder to manage blood sugar levels. The most common infections that precipitate DKA are pneumonia and urinary tract infections, though any serious infection can trigger the condition.^[2]

Missing insulin doses represents the other major cause of DKA. This might happen if someone forgets to take their insulin, if an insulin pump becomes clogged or malfunctions, or if the wrong dose is administered. Sometimes people intentionally skip insulin doses due to various reasons, including psychological factors or concerns about side effects. In newly diagnosed individuals, DKA occurs simply because they haven’t yet started insulin treatment since their diabetes was unknown.^[2]

Other causes and triggers of DKA include serious medical events such as heart attacks or strokes, physical injuries like those from car accidents, and substance use including alcohol or drugs. Certain medications can also increase the risk of developing DKA. These include some water pills (diuretics) and medications called corticosteroids that are used to treat inflammation. Some newer diabetes medications called SGLT2 inhibitors have been associated with DKA in certain circumstances, even when blood sugar levels are not extremely high.^[4]

Risk Factors

Several factors increase the likelihood of developing diabetic ketoacidosis. The most significant risk factor is having type 1 diabetes, as this condition results from the body’s inability to produce insulin. People with type 1 diabetes must rely entirely on injected or inhaled insulin to survive, making them vulnerable to DKA if insulin delivery is interrupted for any reason.^[2]

While less common, people with type 2 diabetes can also develop DKA, particularly those who require insulin therapy or have what is called ketosis-prone diabetes. This risk increases during periods of severe illness or metabolic stress. Additionally, certain demographic groups, particularly obese individuals of Black ancestry with newly diagnosed type 2 diabetes, have been found to experience DKA more frequently than previously recognized.^[4]

Non-compliance with insulin therapy represents a major preventable risk factor. When people don’t follow their prescribed insulin regimen consistently, whether due to forgetfulness, access issues, financial concerns, or psychological reasons, they significantly increase their risk of DKA. Young adults with type 1 diabetes appear to be at particularly high risk, sometimes related to the challenges of managing a chronic condition during a transitional life stage.^[4]

Infections and acute illnesses dramatically raise the risk of DKA. When your body fights an infection or deals with another serious medical condition, it releases stress hormones that work against insulin and raise blood sugar levels. This means your usual insulin dose may not be sufficient during illness. Surgical procedures and traumatic injuries create similar metabolic stress that can precipitate DKA.^[4]

Certain medications increase DKA risk by affecting how the body handles sugar and insulin. Beyond SGLT2 inhibitors, other drugs that can contribute include antipsychotic medications, some blood pressure medications, and drugs that affect the immune system. Alcohol and drug use also increase the risk of DKA through various mechanisms, including interfering with eating patterns and blood sugar regulation.^[4]

Symptoms

The symptoms of diabetic ketoacidosis typically develop over a period of about 24 hours, though they can appear more quickly in some cases. Early recognition of symptoms is crucial because prompt treatment can prevent the condition from becoming life-threatening. For some people, particularly children or those who don’t know they have diabetes, these symptoms may be the very first indication that something is wrong.^[1]

The earliest symptoms of DKA usually include excessive thirst and urinating much more frequently than normal. As your blood sugar rises, your kidneys try to remove the excess sugar through urine, causing you to need to urinate repeatedly. This leads to significant fluid loss, which triggers intense thirst as your body attempts to replace the lost fluids. You may find yourself drinking large amounts of water but still feeling thirsty.^[1]

As the condition progresses, additional symptoms emerge. Many people experience nausea and vomiting, which can make it even harder to maintain proper hydration and blood sugar control. Stomach pain is common and can sometimes be severe enough to be mistaken for other abdominal conditions. You may feel extremely weak, tired, or fatigued, making it difficult to carry out normal daily activities. Some people also experience intense hunger, even as they feel ill.^[2]

One of the distinctive signs of DKA is changes in breathing. You may notice that you’re breathing more rapidly and deeply than usual, a pattern called Kussmaul breathing. Your body does this automatically to try to eliminate some of the acid from your blood through your lungs. Along with this breathing change, your breath may develop a fruity or sweet smell, similar to nail polish remover or pear drops. This unusual odor comes from the ketones in your blood.^[2]

Dehydration becomes increasingly apparent as DKA worsens. Your skin may appear dry and lack its normal elasticity. Your mouth becomes very dry, and your face may appear flushed or reddened. You might experience headaches, and your muscles may feel stiff or achy. These physical signs reflect the significant loss of fluids and electrolytes from your body.^[2]

In more severe cases, mental changes occur. You may feel confused, disoriented, or less alert than normal. Some people describe feeling foggy or having difficulty concentrating. Your level of consciousness may decrease, and in the most serious situations, DKA can lead to loss of consciousness or coma. Any mental changes or decreased alertness indicate a medical emergency requiring immediate attention.^[3]

Prevention

Preventing diabetic ketoacidosis requires awareness, careful monitoring, and consistent management of diabetes. While DKA is serious, it is often preventable through proper diabetes care and early intervention when warning signs appear. Taking proactive steps can significantly reduce your risk of experiencing this dangerous complication.^[2]

The foundation of DKA prevention is taking your diabetes medications, particularly insulin, exactly as prescribed. Even if you’re feeling well, it’s essential to continue your insulin regimen without interruption. Never stop taking insulin or skip doses, even when you’re not eating normally. If you’re having trouble affording your medications or experiencing side effects, talk with your healthcare team about solutions rather than stopping treatment on your own.^[5]

Regular blood sugar monitoring is crucial for catching problems early. Check your blood sugar before meals and at bedtime, or as often as your doctor recommends. This allows you to identify high blood sugar levels before they become dangerous. When your blood sugar is elevated, you can take corrective action such as adjusting your insulin dose according to your healthcare provider’s instructions. Monitoring is particularly important during illness, stress, or any change in your normal routine.^[2]

Testing for ketones is an important prevention tool. Anytime you’re sick or your blood sugar is 240 mg/dL or higher, you should test for ketones using either urine test strips or a blood ketone meter. These tests are available without a prescription at pharmacies. Testing every 4 to 6 hours when you’re ill or have high blood sugar helps you catch rising ketone levels early. If your ketone levels are moderate or high, contact your healthcare provider immediately.^[2]

Managing sick days properly is essential for DKA prevention. When you have an infection, flu, or other illness, your blood sugar control becomes more challenging. Continue taking your insulin even if you’re not eating normally, as illness often raises blood sugar levels. Drink plenty of sugar-free fluids to stay hydrated. Check your blood sugar and ketones more frequently than usual. Contact your healthcare team early during any illness to get guidance on adjusting your insulin doses and managing your diabetes during this stressful time.^[2]

Working with your diabetes care team to create a sick day plan before you become ill helps you know exactly what to do when problems arise. This plan should include instructions on insulin dose adjustments, when to check ketones, how much fluid to drink, and when to seek medical help. Having this information ready means you won’t have to make important decisions while feeling unwell.^[2]

Education plays a vital role in prevention. Diabetes self-management education and support services can provide you with the knowledge and skills needed to manage your diabetes effectively and recognize early warning signs of DKA. These programs teach you how to adjust your care during different situations and empower you to take charge of your health. Ask your healthcare provider for a referral to these valuable services.^[2]

Wearing or carrying medical identification at all times is an important safety measure. If you become very ill or lose consciousness, medical identification alerts emergency responders that you have diabetes, enabling them to provide appropriate treatment quickly. This simple step can be lifesaving in an emergency situation.^[5]

Pathophysiology

Understanding what happens inside your body during diabetic ketoacidosis helps explain why this condition is so serious and why specific treatments are necessary. The changes that occur affect multiple body systems and create a cascade of problems that require urgent correction.^[4]

The process begins with an absolute or relative deficiency of insulin, the hormone that acts like a key to unlock cells and allow sugar to enter for energy. When insulin is insufficient or missing, sugar accumulates in your bloodstream instead of entering cells. This creates hyperglycemia, or abnormally high blood sugar levels. Your liver, sensing that cells aren’t getting energy, responds by producing even more sugar through a process called gluconeogenesis, making the high blood sugar even worse.^[3]

Because cells cannot access sugar for energy without adequate insulin, your body shifts to an alternative energy source: fat. The liver breaks down fat rapidly to create fuel, but this process produces ketones as a byproduct. Under normal circumstances, when you haven’t eaten for a while, your body produces small amounts of ketones safely. However, in DKA, ketones are produced at an extremely rapid rate. These ketones, which are acidic substances, accumulate in your blood faster than your body can eliminate them.^[3]

The buildup of ketones causes your blood to become acidic, a condition called metabolic acidosis. This acidity disrupts the normal pH balance your body needs to function. Your blood normally has a slightly alkaline pH, and when it becomes too acidic, many of your body’s chemical processes don’t work properly. Enzymes that control metabolism become less effective, and cellular functions throughout your body are impaired.^[3]

The extremely high blood sugar levels cause water to move out of your cells through osmosis, leading to intracellular dehydration, where cells become depleted of water. Initially, this water movement increases the volume of fluid outside cells, which can cause your sodium level to appear low. However, as your kidneys try to eliminate the excess sugar through urine, you begin losing large amounts of both water and electrolytes.^[14]

This excessive urination leads to progressive dehydration and volume depletion throughout your body. As you become more dehydrated, your kidneys produce less urine, which means sugar and ketones remain in your blood at even higher concentrations. The dehydration also affects your circulation, potentially causing your blood pressure to drop. Your heart rate increases as your cardiovascular system tries to maintain adequate blood flow to vital organs despite the reduced fluid volume.^[14]

Electrolyte imbalances develop as your body loses minerals through excessive urination and vomiting. Potassium, sodium, and other essential electrolytes (minerals that carry electrical charges and are crucial for nerve and muscle function) become depleted. While your blood potassium level might appear normal or even high initially due to the acidic blood causing potassium to shift out of cells, your total body potassium is actually severely depleted. This becomes particularly important during treatment, as correcting the acidosis causes potassium to move back into cells, which can cause blood levels to drop dangerously low.^[11]

Your body attempts to compensate for the acidosis by increasing your breathing rate and depth. This rapid, deep breathing pattern helps eliminate carbon dioxide from your blood, which slightly reduces the acidity. However, this compensatory mechanism alone cannot overcome the severe acid buildup from ketones. The distinctive fruity-smelling breath occurs because one type of ketone, called acetone, is eliminated through your lungs.^[14]

The hormonal imbalances that trigger DKA involve not only lack of insulin but also increased levels of counter-regulatory hormones. These hormones—including glucagon, cortisol, growth hormone, and catecholamines—normally help raise blood sugar during times of stress or fasting. In DKA, elevated levels of these hormones work against any remaining insulin, making blood sugar control even more difficult. They also promote the breakdown of fat and protein, contributing to ketone production.^[4]

The combination of hyperglycemia, acidosis, dehydration, and electrolyte imbalances creates a life-threatening situation. These metabolic derangements affect every organ system. Your brain function becomes impaired, potentially leading to confusion or loss of consciousness. Your heart’s electrical and mechanical function can be disrupted by electrolyte imbalances. Your kidneys struggle to maintain proper filtering and fluid balance. Without rapid treatment to restore insulin, fluids, and electrolytes, these changes can progress to organ failure, coma, and death.^[3]