Diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic state (HHS) are two serious complications of diabetes that are potentially life threatening. Both involve a dangerous rise in sugar levels, but only DKA is linked to high ketone levels.
DKA is usually associated with type 1 diabetes, whereas people with type 2 diabetes are at risk of HHS.
Both conditions occur as a result of an insulin deficiency that causes hyperglycemia.
This article reviews the differences and similarities between DKA and HHS.

DKA and HHS have some similar features. They both result from an issue with insulin that causes an unsafe rise in blood sugar levels.
DKA is
As a result of this deficiency, the liver starts to break down fats for energy instead of sugar. As part of this process, it creates chemicals called ketones. The number of ketones can rapidly become too high, creating a potentially dangerous situation for the person.
HHS
Both conditions can be life threatening if a person does not receive immediate care.
Learn moreLearn more about diabetic emergencies.
The table below shows the causes, symptoms, and treatment of DKA and HHS. It also compares the
Condition | Primarily affects | Possible causes | Treatment options | Mortality rate | Symptoms |
---|---|---|---|---|---|
DKA | people with type 1 diabetes | • illness • missing an insulin dose • cardiac event • heavy alcohol use • injury | IV delivery of: • fluids • insulin • electrolytes • medications for illness | up to 2% | • fruity-smelling breath • high ketone levels in urine • symptoms present within a few hours |
HHS | people with type 2 diabetes | • illness • cardiac event | IV delivery of: • fluids • insulin • electrolytes • medications for illness | up to 20% | • fast heart rate • neurological symptoms such as confusion • symptoms present over days or weeks |
DKA and HHS can present with similar symptoms.
The early stages of both conditions cause:
DKA
The symptoms of DKA can
- dry skin and mouth
- fruity smelling breath
- flushed face
- fast, heavy breathing
- excessive tiredness
- headaches
- muscle stiffness or aches
- stomach pain
- nausea and vomiting
HHS
HHS
The symptoms of HHS can include:
- malaise, or a general feeling of illness
- fatigue
- weakness
- dehydration, which can involve dryness of the mouth, eyes, or lips
One distinguishing characteristic is that HHS can cause neurological signs and symptoms, which may include:
Finally, HHS can also present with symptoms related to its cause. Sometimes, a person may develop HHS following an infection or a cardiac event, such as a heart attack or stroke.
If an infection causes HHS, a person might also experience:
- tachycardia, or a fast heart rate
- general weakness
- abnormally rapid breathing
- fever
If a cardiac event causes HHS, a person might also experience:
- heart palpitations
- headaches
- chest pain and tightness
DKA and HHS can present similarly, as many of their symptoms overlap.
However, one key difference is the presence of neurological symptoms. HHS can cause a person to experience hallucinations, confusion, drowsiness, loss of vision, or a coma.
Both conditions cause an unsafe level of blood sugar. However, DKA
Both conditions may result from similar factors, such as:
- medication use
- illness
- cardiac events
However, DKA can occur due to a missed insulin dose, heavy alcohol use, or a physical injury.
Although both conditions can lead to diabetic coma and death, the mortality rate of HHS is
The causes of both DKA and HHS are similar. Both may occur due to:
- illness
- a cardiac event, such as a heart attack or stroke
- issues with diabetes medications, such as missing a dose or taking too much or too little
- the use of certain other medications, such as diuretics
However, the most common causes are different.
For HHS, the most common cause is an infection, which accounts for at least
The two
The treatments for DKA and HHS are similar. Doctors will typically recommend the use of an IV line to deliver:
- electrolytes
- fluids
- insulin
- medications to treat any underlying conditions, such as antibiotics for bacterial infections
A doctor may discuss ongoing diabetes management with the person, including any necessary changes to their diet and exercise regimen. They may also adjust the person’s medications.
A person can take steps at home to help prevent the development of either DKA or HHS. These
- monitoring blood glucose levels frequently, particularly when sick
- taking medications on time and according to the prescription
- keeping blood glucose levels within a target range
- discussing adjustments to medication or insulin based on dietary or exercise-related changes
DKA and HHS are emergencies that require immediate medical attention. A person living with diabetes should seek emergency care if they develop symptoms of either condition.
It is also advisable for a person to test their blood sugar levels if they start to have early warning signs of hyperglycemia, such as extreme thirst or frequent urination.
Below are the answers to common questions about DKA and HHS.
Which is worse out of DKA and HHS?
Both DKA and HHS can be life threatening and require prompt treatment. However, HHS has a fatality rate that is about
What is the difference between HONK and HHS?
HONK stands for hyperglycemic hyperosmolar non-ketotic coma, which is how the medical community previously referred to HHS.
Non-ketotic hyperglycemic coma and hyperosmolar hyperglycemic non-ketotic syndrome are two other former names for the condition.
DKA and HHS are two complications of diabetes that have similar symptoms, causes, and treatments. Both conditions result from high blood glucose levels and require insulin to help treat them.
DKA typically affects people living with type 1 diabetes, whereas HHS usually occurs in people living with type 2 diabetes. HHS tends to be more dangerous than DKA, but both conditions can be deadly if a person does not receive treatment.
Prompt medical attention is necessary in both cases. A person should seek emergency medical care if they develop symptoms that could indicate HHS or DKA.