Diabetic hyperosmolar syndrome can take days or weeks to develop. Possible signs and symptoms include:

• Blood sugar level of 600 milligrams per deciliter (mg/dL) or 33.3 millimoles per liter (mmol/L) or higher
• Excessive thirst
• Dry mouth
• Increased urination
• Warm, dry skin
• Fever
• Drowsiness, confusion
• Hallucinations
• Vision loss
• Convulsions
• Coma

Diabetic hyperosmolar syndrome may be triggered by:

• Illness or infection
• Not following a diabetes treatment plan or having an inadequate treatment plan
• Certain medications, such as water pills (diuretics)

Sometimes undiagnosed diabetes results in diabetic hyperosmolar syndrome.

Your risk of developing diabetic hyperosmolar syndrome might be higher if you:

• Have type 2 diabetes. If you don't monitor your blood sugar or you don't yet know you have type 2 diabetes, your risk is higher.
• Are older than age 65.
• Have another chronic health condition, such as congestive heart failure or kidney disease.
• Have an infection, such as pneumonia, a urinary tract infection or a virus, which causes your blood sugar levels to rise.
• Take certain medications. Some drugs — such as corticosteroids (prednisone), diuretics (hydrochlorothiazide and chlorthalidone) and the anti-seizure medication phenytoin (Dilantin).

Diabetic hyperosmolar syndrome can lead to:

• Seizures
• Heart attack
• Stroke
• Coma