Diabetes certainly has its share of potential long-term complications, such as cardiovascular disease or vision problems, but people with diabetes can also be at immediate risk for a sudden, dangerous condition called diabetic ketoacidosis (DKA).
Here’s how ketoacidosis develops: Normally, the hormone insulin helps the body use blood sugar, or glucose, for energy; with diabetes, insulin production is impaired. If insulin gets too low, your body can’t use glucose for fuel.
“The body sees this as a state of starvation and, as a result, starts metabolizing fat and muscle to make ketones, a metabolic fuel we normally use when we are fasting,” says Joseph Aloi, MD, section chief of endocrinology and metabolism at Wake Forest Baptist Medical Center. “Ketones are acidic and can build up to high levels.” If this happens, it can be toxic.
(By the way, diabetic ketoacidosis and ketosis—in which ketones build up from, say, being on a low-carb diet—are two very different things. Ketosis isn’t usually harmful or life-threatening; diabetic ketoacidodis is.)
DKA is more common in people with type 1 diabetes, who can’t make any insulin on their own, although it can happen with type 2 diabetes as well. (Here’s more about the difference between type 1 and type 2 diabetes.)
But even people who haven’t been diagnosed with diabetes should be aware of the condition, because diabetic ketoacidosis can often be the first sign you have diabetes.
For people with diabetes, DKA is more likely to strike at certain times when insulin levels tends to drop. For example, “during illness, the stress of being sick increases your insulin requirements,” Dr. Aloi says. “Missed doses of insulin can also lead to insulin deficiency, and is a very common problem as the price of insulin has escalated.” Pregnancy increases insulin requirements as well, he says. Skipping a meal or not consuming enough food may also lead to DKA development.
Here are the symptoms of diabetic ketoacidosis to look for:
“Excess blood sugar and ketones both act at the kidney as a diuretic to increase urination,” Dr. Aloi says. “The excess urination leads to dehydration and excess thirst, making it difficult to drink and keep up with fluid intake.” The average patient with diabetic ketoacidosis has lost five liters of fluid before being treated, he says.
As ketones build up, they begin to take their toll on your body. “The high levels of ketones can cause nausea and emesis [vomiting],” Dr. Aloi says. “The high blood sugar slows stomach emptying, which causes nausea, and the acidosis can make this worse and cause abdominal pain.” Continuous vomiting leads to further dehydration and loss of electrolytes.
If you start feeling totally out of it, that could be DKA. “As dehydration persists, other electrolytes and minerals like potassium and phosphorus becomes low, which makes muscles weak,” Dr. Aloi says. If left untreated, diabetic ketoacidosis can cause unconsciousness and diabetic coma.
“To get rid of the acid, the body tries to excrete it from the kidneys, which are overloaded, so the only other option is to get rid of it through the lungs, increasing respirations,” Dr. Aloi says. This “can double or triple the respiratory rate, so you feel short of breath.”
That extra, shallow breathing will often have a particular smell. “As the ketones are ‘evaporated’ through the lungs, they have a fruity, sweet odor,” Dr. Aloi says.
The first step to avoiding DKA is to be prepared. Take your insulin and monitor your blood sugar as directed by your doctor—and if you’re sick, check it more often (as much as every three or four hours). In addition, when you’re ill or if your blood sugar is high, check your ketones every four to six hours. You can check your ketone levels at home with urine testing kits (available at the drugstore).
Come up with a “sick day” plan with your doctor or diabetes educator, and make sure you have urine testing kits at the ready. “Moderate to high ketones on a test strip and nausea are a reason to seek medical attention—even if your blood sugar is not very elevated,” says Dr. Aloi. If your blood sugar is ever elevated—over 250 mg/dL for no apparent reason—you should also test your ketones, he says.
If your ketones are high, call your doctor. Be sure not to exercise when you suspect you might have ketoacidosis, as that requires more energy and will cause your body to make more ketones. (Here are more rules for exercising safely with diabetes.)
If you’re already having symptoms of DKA, go to the ER. At the hospital, you’ll receive “lots of IV fluids, electrolyte replacement of potassium and phosphorus, and IV insulin or frequent injections of insulin every two to four hours,” Dr. Aloi says. “If the acid level is very high, your blood pH can become dangerously low and commonly requires an ICU stay for cardiac monitoring.” The combination of low potassium, dehydration and acidosis can make the heart prone to an irregular rhythm, he says.
Although DKA is treatable, it’s important to get prompt care if you think you may be experiencing it.
“The Centers for Disease Control and Prevention [CDC] released a 2018 report showing the rate of hospitalizations for DKA has climbed 54.9 percent from 2009 to 2014,” Dr. Aloi says. But, he points to new insulin management technology in the ER that may lessen the likelihood you’ll be admitted to the hospital.
In any case, taking steps to avoid getting DKA—and knowing the signs of diabetic ketoacidosis—is key. “Diabetic ketoacidosis is a life-threatening, but preventable complication of diabetes,” he says.
Here's more advice about avoiding diabetes complications: