Diabetic hyperosmolar syndrome

Diabetic hyperosmolar (hi-pur-oz-MOE-lur) syndrome is a serious condition that develops when your blood sugar reaches a very high level. When your blood sugar gets to this level, your blood becomes thick and syrupy, causing diabetic hyperosmolar syndrome. Excess sugar passes from your blood into your urine, triggering a filtering process that draws tremendous amounts of fluid from your body.

Diabetic hyperosmolar syndrome usually affects people with type 2 diabetes, and may develop in people who haven't yet been diagnosed with diabetes.

Left untreated, diabetic hyperosmolar syndrome can lead to life-threatening dehydration. Prompt medical care is essential.

Symptoms Causes Risk factors Complications Prevention

Diabetic hyperosmolar syndrome may take days or even weeks to develop.  Pay attention to possible signs and symptoms, which include:

  • High blood sugar level
  • Excessive thirst
  • Dry mouth
  • Increased urination
  • Warm, dry skin with no sweating
  • Fever
  • Sleepiness
  • Confusion
  • Hallucinations
  • Vision loss
  • Weakness on one side of the body
  • Convulsions
  • Coma

When to see a doctor

Consult your doctor if your blood sugar is persistently higher than the target range your doctor has recommended, or if you experience any signs or symptoms of diabetic hyperosmolar syndrome, such as:

  • Excessive thirst
  • Increased urination
  • Warm, dry skin without sweating
  • Dry mouth
  • Fever

Seek emergency care if:

  • Your blood sugar level is 600 milligrams per decileter (mg/dL), or 33.3 millimoles per liter (mmol/L) or higher
  • You experience confusion, vision changes or weakness on one side of the body

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