First Aid Phraseology: Insulin Shock vs. Diabetic Coma

Sometimes in medical care—especially first aid—we try to make the terminology more user-friendly. It’s led to terms like heart attack or stroke (and in recent years stroke has been increasingly called “brain attack”). Some of the terms make sense, but there are others that simply don’t work for anyone other than the doctors who thought them up in the first place.

Man checking his blood sugar on a device
Mark Hatfield / Getty Images

Insulin shock and diabetic coma are two terms that just don’t make sense.

Insulin shock refers to the body’s reaction to too little sugar (hypoglycemia) often caused by too much insulin. Diabetic coma refers to a victim of high blood sugar (hyperglycemia) who becomes confused or unconscious.

These terms are confusing, and not because my blood sugar is too low. They don’t have any connection to reality. Indeed, if I was nicknaming medical conditions today, I would switch these.

Insulin Shock

Insulin shock makes it sound like the body is in shock, which isn’t true. Shock is, first and foremost, a lack of blood flow to important areas of the body, like the brain. It usually comes with very low blood pressure. The most common symptom of low blood sugar is confusion (yeah, I know, that’s supposed to go with diabetic coma—just stay with me here), not low blood pressure. In fact, insulin shock doesn’t affect the blood pressure much at all.

Insulin shock also implies that insulin is to blame, but insulin—at least from injections—is not required for someone to develop low blood sugar. Plenty of diabetics take pills, which do not contain insulin, to control their blood sugar levels. Some diabetics control their blood sugar levels simply by watching their diets. To make it even worse, some folks get low blood sugar even though they’re not diabetic at all, which means they would have no reason to take insulin or pills (although they do have to check their blood sugar levels).

So why is it called insulin shock? Because it sort of looks like shock. Shock—the real, low blood pressure kind—causes the body to react with what’s known as the “fight or flight syndrome.” Low blood sugar does the same thing. The fight or flight syndrome Syndrome is the body’s normal reaction to any stress. It makes us ready to run away or fight for our lives. It causes our hearts to beat faster and it makes us sweat.

Having too little blood, too little oxygen or too little sugar all make your brain scared enough to get your body ready to do battle or run away. That’s where the name comes from, but it sure doesn’t explain much about the problem. Indeed, it makes the word shock even fuzzier in the medical lexicon. Shock already refers to electrical therapy, low blood pressure, and emotional trauma. Thanks to this terminology, it also refers to severely low blood sugar, even though the official word for that is hypoglycemia.

Diabetic Coma

At least with insulin shock, the patient usually knows about her diabetes. Diabetic coma, on the other hand, creeps up on you. It takes a lot of sugar in the bloodstream to reach confusion and unconsciousness. That doesn’t happen overnight.

Worse, high blood sugar stimulates the production of urine—lots of urine. One of the symptoms of high blood sugar is frequent urination. Victims can urinate so often they become dehydrated, which can lead to shock.

The term “diabetic coma” came along in the 19th century, before the ability to quickly and accurately measure blood sugar was available. In those days, the first sign of diabetes might be unconsciousness. Even a patient’s doctor didn’t know they were diabetic until the confusion set in. Even today, diabetic coma is most likely to happen to those who don’t know they’re diabetic yet, but if you listen to your body, the warning signs are surely there long before confusion sets in.

Okay, so follow along with me here: Insulin shock causes confusion and unconsciousness very quickly and is not shock at all, but diabetic coma only causes unconsciousness after several days—maybe weeks—and leads to dehydration severe enough in some people to be considered shock.

Yeah. I agree. In today’s world, those are pretty dumb names.

3 Sources
Verywell Health 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. American Diabetes Association. Hypoglycemia (low blood sugar).

  2. American Diabetes Association. Hyperglycemia (high blood glucose).

  3. Pasquel FJ, Umpierrez GE. Hyperosmolar hyperglycemic state: a historic review of the clinical presentation, diagnosis, and treatment. Diabetes Care. 2014;37(11):3124-3131. doi:10.2337/dc14-0984

By Rod Brouhard, EMT-P
Rod Brouhard is an emergency medical technician paramedic (EMT-P), journalist, educator, and advocate for emergency medical service providers and patients.