Why Diabetes Can Sometimes Look Like the Flu

How to recognize severe complications that might look like the flu.

In the U.S., 30.3 million people, or 9.4 percent of the population, had diabetes in 2015. More than 1 in 4 of them didn’t know they had the disease.  And the number is growing, with two million adults newly diagnosed every year.

While the most common complications of diabetes, such as heart attack and stroke, can be years in the making, other severe complications can come on suddenly and may even be mistaken for something as commonplace as the flu. Learn how to recognize the symptoms

What Is Diabetes?

Also called blood sugar, diabetes is a disease that occurs when your blood glucose is too high. Blood glucose is your main source of energy and comes from the food you eat. When an individual has diabetes, the pancreas doesn’t make any, or makes very little, insulin (a hormone responsible for helping blood sugar enter cells where it can then be used as energy) and so blood sugar levels go up.

Over time, having too much glucose in your blood can cause health problems such as kidney disease, heart disease, stroke, foot problems, eye disease, and others. Although diabetes has no cure, you can take steps to manage your diabetes and stay healthy.

Flu-like Diabetes Complications

Uncontrolled high blood sugar can cause both diabetic ketoacidosis and diabetic hyperglycemic hyperosmolar syndrome (HHS), both of which can lead to a diabetic coma, which can be fatal.

“Patients become sluggish. They feel out of it. They become tired. Their muscles are aching,” Spyros Mezitis, MD, PhD, an endocrinology consultant and clinical investigator at Lenox Hill Hospital in New York City, told Health. “This state is a life-threatening emergency,” said Dr. Mezitis.

Diabetic hyperosmolar syndrome is more often seen in type 2 diabetics. Diabetic HHS happens when the body has extremely high blood sugar levels, without the presence of ketones.

With diabetic hyperosmolar syndrome, your body tries to get rid of excess blood sugar by increasing urine output. This can lead to severe dehydration which, in extreme cases, leads to seizures, coma, or even death.

Symptoms of diabetic hyperosmolar syndrome may include any of the following:

  • Increased thirst and urination (at the beginning of the syndrome)
  • Feeling weak
  • Nausea
  • Weight loss
  • Dry mouth, dry tongue
  • Fever
  • Seizures
  • Confusion
  • Coma

In diabetic ketoacidosis or DKA, a lack of insulin causes the body to burn fat, leading to a toxic build-up of acids called ketones in the blood.

Common symptoms of DKA can include:

  • Decreased alertness
  • Deep, rapid breathing
  • Dehydration
  • Dry skin and mouth
  • Flushed face
  • Frequent urination or thirst that lasts for a day or more
  • Fruity-smelling breath
  • Headache
  • Muscle stiffness or aches
  • Nausea and vomiting
  • Stomach pain

Either way, the symptoms of both diabetic hyperosmolar syndrome and DKA are similar and may be dangerously misleading.

Diabetes and the Flu

People with diabetes and the flu may be at an even higher risk of falling into a diabetic coma as an infection (either influenza or something else), can cause blood sugar levels to spike.

“In a diabetic who’s not controlled, who’s not taking insulin correctly, they’re not compliant [with their medication], the sugar goes up fast and on top of that if he or she has the flu, you can have serious trouble with hyperosmolar syndrome,” said Dr. Mezitis.

How to Avoid Complications

You can manage your diabetes and live a long and healthy life by taking care of yourself each day. With the help of your healthcare team, you can create a diabetes self-care plan to manage your diabetes. In addition, you can do the following to minimize your risk of developing dangerous complications from diabetes:

  • Watch for diabetes symptoms and get tested if you're at risk. Symptoms can include urinating a lot (particularly if you have to get up at night to go) or severe thirst, although many people have no symptoms at all. (Ask your healthcare provider if you're at risk and have your blood sugar tested.)
  • If you have been diagnosed with type 2 diabetes, make sure you keep your blood sugar under control by eating right, exercising, and taking medication if necessary. People with type 2 can take pills or injections of insulin or other drugs to control blood sugar. (People with type 1 have fewer options and need to take insulin to survive.)
  • For people at risk of type 2 diabetes, exercise may be the single best way to avoid diabetes, or at least avoid complications.
  • In addition to lifestyle interventions, many people with type 2 diabetes take medications to control their blood sugar and, in some cases, even insulin to help get glucose out of the bloodstream and into the fat where it’s stored until needed.
  • Get your flu shot every year. That goes for diabetics and non-diabetics alike. The CDC recommends that all people over the age of 6 months get vaccinated, especially those with compromised immune systems, such as people with diabetes, as well as people over the age of 65.

A Quick Review

Diabetes affects millions of Americans, and the number is on the rise. While diabetes can often be managed with a diabetes self-care plan, complications can arise from the disease. Some complications such as diabetic ketoacidosis and diabetic hyperglycemic hyperosmolar syndrome may even be mistaken for something as commonplace as the flu but can be fatal.

People with diabetes and the flu may be at an even higher risk of falling into a diabetic coma, which makes it essential to keep track of symptoms and manage your diabetes with your healthcare team.

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Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). What is diabetes?

  2. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Preventing Diabetes.

  3. Medline Plus. Diabetic hyperglycemic hyperosmolar syndrome.

  4. CDC. Who needs a flu vaccine.

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