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Quick Facts

Hyperosmolar Hyperglycemic State


The Manual's Editorial Staff

Last full review/revision May 2021| Content last modified May 2021
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What is hyperosmolar hyperglycemic state (HHS)?

Hyperosmolar hyperglycemic state (HHS) is a serious complication caused by diabetes. Diabetes is a disease in which your blood sugar (glucose) levels are too high.

Hyperosmolar means your blood is too concentrated. Hyperglycemic means your blood sugar is too high.

  • HHS is a complication of type 2 diabetes

  • You get very dehydrated, which can cause confusion, coma, seizures, and death

  • Treatment is fluids in your vein and insulin

What causes HHS?

HHS is caused by very high blood sugar levels, usually in people with type 2 diabetes. People with type 1 diabetes don't usually get HHS. They may get diabetic ketoacidosis instead. The extremely high levels of blood sugar cause you to pass much more urine than usual. This causes severe dehydration and makes your blood more concentrated.

You're more likely to get HHS if you have type 2 diabetes and you:

  • Are older

  • Stop your diabetes medicine

  • Get an infection or another stress to your body such as a heart attack, stroke, or surgery

  • Aren't drinking enough fluids or tend not to feel thirsty

  • Have kidney problems

  • Take certain medicines, such as corticosteroids and diuretics

What are the symptoms of HHS?

The first symptoms are:

  • Urinating (peeing) a lot

  • Dry mouth and dry skin

  • Feeling very thirsty

  • Mental changes, such as confusion or extreme sleepiness

If not treated early, you may also have:

How can doctors tell if I have HHS?

Doctors may think you have HHS if you have diabetes and seem confused. They tell for sure by doing:

  • Blood and urine tests

How do doctors treat HHS?

Doctors treat you in the hospital with:

  • Fluids and electrolytes (minerals necessary to make your body work normally) into your vein

  • Insulin into your vein

  • Frequent blood tests to make sure your blood sugar and electrolytes are going back to normal

Doctors also treat whatever other problem caused the HHS.

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