Generally, diabetic ketoacidosis (DKA) develops slowly. However, when it develops, immediate medical attention is required. If left untreated, DKA may result in pneumonia, shock, diabetic coma and even death. Small children may also develop swelling of the brain (cerebral edema), with a headache as the earliest symptom. Certain signs and symptoms of DKA appear earlier than others. These include:

• High levels of glucose (blood sugar). Hyperglycemia is an important warning sign of DKA. Levels above 250 mg/dL are typically considered high, but individuals are advised to consult their physician about what level of glucose is considered excessive for them.
  
  
• Higher-than-normal levels of ketones in urine.
  
  
• Extreme thirst (polydipsia) or dry mouth.
  
  
• Frequent urination (polyuria). In children, this may take the form of bedwetting.
  
  
• Breathing difficulties. People with DKA may experience fast, deep or labored breathing, known as Kussmaul breathing or air hunger. However, as the level of ketones increase, the breathing may become deeper and slower.

Other DKA signs and symptoms may develop later. These include:

• Fatigue.
  
  
• Warm, dry or flushed skin.
  
  
• Nausea and vomiting. It is important to notify a physician if vomiting lasts longer than two hours. DKA may develop within a matter of hours after vomiting.
  
  
• Abdominal pain. This may also include tenderness and a lack of bowel sounds.
  
  
• A sweet, fruity odor on the breath.
  
  
• Confusion or difficulty paying attention.

People with diabetes should notify their physician if they develop any of these signs or symptoms. If levels of ketones and glucose are high, diabetic individuals are advised to avoid exercising, as the body does not have enough insulin to supply the muscles with fuel. As a result, fat, and not glucose, is used for fuel, and additional ketones are formed. DKA may be life-threatening, so prompt treatment is crucial.