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

Diabetic hyperosmolar syndrome may be triggered by:

  • Illness
  • An underlying infection, such as pneumonia, dental or a urinary tract infection
  • Not following your diabetes treatment plan
  • Certain medications, such as water pills (diuretics)

Sometimes undiagnosed diabetes results in diabetic hyperosmolar syndrome.

Certain factors raise your risk of developing diabetic hyperosmolar syndrome, such as:

  • Having type 2 diabetes. Although people with type 1 diabetes can be affected, hyperosmolar syndrome is much more common in people with type 2 diabetes.  If you have type 2 diabetes, and you don't monitor your blood sugar or you don't yet know you have type 2 diabetes, you have an even higher risk.
  • Being middle-aged or older. If you're in these age groups, you're more likely to develop diabetic hyperosmolar syndrome.
  • Having another chronic health condition. Your risk of hyperosmolar syndrome is increased if you have another chronic illness, such as congestive heart failure or kidney disease.
  • Having an infection. Having an illness, such as pneumonia or a virus, causes your blood sugar levels to rise and can increase your risk of diabetic hyperosmolar syndrome.
  • Taking certain medications. Some drugs — such as corticosteroids (prednisone), diuretics (hydrochlorothiazide and chlorthalidone) and the anti-seizure medication phenytoin (Dilantin) — can increase your risk of developing hyperosmolar syndrome.

Diabetic hyperosmolar syndrome can lead to:

  • Convulsions
  • Heart attack
  • Stroke
  • Coma

Without prompt treatment, diabetic hyperosmolar syndrome can be fatal.

Good day-to-day control of your diabetes can help you prevent diabetic hyperosmolar syndrome. Keep these tips in mind:

  • Know the symptoms of high blood sugar. Be alert for the warning symptoms of high blood sugar, as well as the situations that put you at risk of developing hyperosmolar syndrome, such as illness.
  • Follow your meal plan. Consistent snacks and meals can help keep your blood sugar level steady.
  • Keep an eye on your blood sugar level. Blood sugar monitoring can tell you whether you're keeping your blood sugar level in your target range — and alert you to dangerous highs, especially if you have an infection. Ask your doctor how often you should test your blood sugar.
  • Take your medication as directed. If you have frequent episodes of high blood sugar, let your doctor know. He or she may need to adjust the dosage or timing of your medication.
  • Exercise regularly. Regular physical activity can help keep your blood sugar levels from going too high. Talk with your doctor before beginning any exercise plan, but for most people, experts recommend 150 minutes of moderate intensity exercise a week — about 30 minutes a day.
  • Educate your loved ones, friends and co-workers. Teach loved ones and other close contacts how to recognize early signs and symptoms of blood sugar extremes — and how to summon emergency help should you pass out.
  • Wear a medical ID bracelet or necklace. If you're unconscious, the ID can provide valuable information to your loved ones, co-workers and others — including emergency personnel.
  • Stay up to date on your vaccinations. Be sure to get an annual flu shot, and ask your doctor if you need the pneumococcal vaccine, which protects against some forms of pneumonia.
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