Hyperosmolar Hyperglycemic State

What is hyperosmolar hyperglycemic state?

Hyperosmolar hyperglycemic state (HHS) is a life-threatening emergency caused by high blood sugar (hyperglycemia). It causes severe dehydration and the blood becomes very thick. Without prompt treatment HHS can be fatal.

How does it occur?

HHS is most common in adults with type 2 diabetes. Because type 2 diabetes can be a silent disease for many years if the blood sugar is not checked, HHS may happen in people whose diabetes has never been diagnosed.


Most people with HHS have a blood sugar level over 600 mg/dL, which is several times higher than a normal blood sugar. When the kidneys detect this high blood sugar, they try to get rid of the extra sugar by putting more sugar into the urine. But this makes you urinate more and you become dehydrated from the loss of fluid. As you become more dehydrated, your blood becomes thicker and more concentrated. As the blood becomes thicker, the level of sugar in the blood gets even higher, too high for the kidney to be able to fix it. As you become more ill, you are less likely to be able to drink the water that can help treat this severe problem. With the high blood sugar and dehydration comes an imbalance of minerals, especially sodium and potassium, which can lead to problems with the brain and heart.


The two most common reasons for HHS are:

  • not taking diabetes medicines as prescribed
  • getting an infection.

If you are diabetic and have an infection, your blood sugar often rises above your usual levels. However, you may not know that you have an infection because many types of infections have few or no symptoms, at least in the early stages. This is especially true for older adults. This is one reason why regular home monitoring of blood sugar is so important. If the infection and rising blood sugar levels are not detected and treated, the dangerous hyperosmolar hyperglycemic state can develop.


There are many other medical reasons that can cause blood sugars to get dangerously high. For example:

  • If you are taking a diuretic (water pill) for high blood pressure, and you are a diabetic but not checking your blood sugar regularly, your blood sugar can become high over time.
  • If you are depressed or you are older and getting forgetful, you may forget to take your medicine or to check your blood sugar.
  • Drug or alcohol abuse can also put you at great risk for developing HHS.

What are the symptoms?

The most common early symptoms are:

  • tiredness
  • blurry vision
  • dry mouth
  • confusion, especially in older adults.

Other possible symptoms are:

  • muscle cramps
  • fever.

Eventually there is a loss of mental function, starting with confusion and disorientation. This can worsen to seizures and coma. When HHS causes a coma, it is called hyperosmolar nonketotic diabetic coma.

How is it diagnosed?

Your medical history is very important. However, in the case of an emergency, the most important information for diagnosis comes from blood tests: tests of blood sugar, blood count, kidneys (BUN, creatinine), minerals (sodium and potassium), and blood pH (the acid-base balance of the blood). There are also special tests to check the concentration (thickness) of the blood.


The next level of diagnosis is to look for infection that might have caused the HHS. Blood cultures, urine cultures, and a chest X-ray are the usual first tests for infection.

How is it treated?

The first emergency treatment is to give intravenous (IV) fluids. The second is to give continuous insulin in a vein to bring the blood sugar down. The sodium and potassium levels need to be brought back to normal. When you have HHS, you need to be closely checked for brain swelling, kidney failure, and other serious problems. This usually means you need to be in an intensive care unit at the hospital for at least the first day or two.


Once the emergency phase has passed, treatment will continue for any infection or other medical problems that might have helped cause the HHS.

How long will the effects last?

HHS can cause severe dehydration. Severe dehydration can cause blood clots anywhere in the body. For example, if you have a blood clot in the brain, you may have a stroke. A blood clot in the heart can cause a heart attack. If you develop blood clots in the intestines, you will need surgery. Recovery from these kinds of problems can take weeks to months.


How long it takes to recover from HHS depends on how healthy you are to begin with and how bad the complications are. An otherwise healthy person with no medical problems other than diabetes and no HHS complications may take only a few days to recover. A person with other medical problems or HHS complications can take much longer to recover. Some complications may be permanent. If your kidneys fail, you may need to start having dialysis. Brain swelling can cause permanent loss of mental abilities, seizures, or death.

How can I take care of myself?

It is very important for you to learn or relearn how to care for diabetes, including:

  • taking all medicines as prescribed
  • checking blood sugars as often as recommended by your provider
  • keeping regular appointments with your provider
  • calling your provider right away if your blood sugars start rising or you have symptoms of infection.

What can I do to prevent HHS?

The best way to prevent HHS is to:

  • Take your diabetes medicines exactly as prescribed.
  • Talk with your healthcare provider if you have questions about your care.
  • Use your home glucose monitor to check your blood sugar as often as your provider recommends.
  • Keep your regular appointments with your provider (usually every 3 months).
  • Report unexplained high blood sugars to your provider (ask at what sugar level you should call).
  • Report any symptoms of infection, such as fever, a cough, or cloudy urine right away to your provider.
  • Check your blood sugar every 4 hours when you are sick. Work with your healthcare provider to develop a sick-day plan.

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Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.


HIA File ENDO3913.HTM Release 11.0/2008

© 2008 RelayHealth and/or its affiliates. All rights reserved.

2008 RelayHealth and/or its affiliates. All rights reserved.