Insulin Shock and Insulin Reactions

Medically Reviewed by Dany Paul Baby, MD on February 24, 2023
5 min read

Severe hypoglycemia, or insulin shock, is a serious health risk for anyone with diabetes. Also called insulin reaction, because of too much insulin, it can occur anytime there is an imbalance between the insulin in your system and the amount of food you eat, or your level of physical activity. It can even happen while you are doing all you think you can do to manage your diabetes.

The symptoms of insulin shock may seem mild at first, but they should not be ignored. If it isn't treated quickly, hypoglycemia can become a very serious condition that causes you to faint, requiring immediate medical attention. Insulin shock can also lead to a coma and death. It's important that not only you but also your family and others around you learn to recognize the signs of hypoglycemia and know what to do about them. It could save your life.

Hypoglycemia refers to a low level of blood sugar. The cells in your body use sugar from carbohydrates for energy. Insulin, which normally is made in the pancreas, is necessary for sugar to enter the cells. It helps keep the levels of sugar in the blood from getting too high.

It's important to maintain the proper level of sugar in your blood. Levels that are too high can cause severe dehydration, which can be life-threatening. Over time, excess sugar in the body does serious damage to organs such as your heart, eyes, and nervous system.

Ordinarily, the production of insulin is regulated inside your body so that you naturally have the amount of insulin you need to help control the level of sugar. But if your body doesn't make its own insulin or if it can't effectively use the insulin it does produce, you need to inject insulin as a medicine or take another medication that will increase the amount of insulin your body does make. So, if you need to medicate with insulin, it becomes your responsibility to see that you have the amount of insulin you need.

When to take insulin or another medication and how much to use depends on when, what, and how much food you eat. It also depends on your level of physical activity since the cells in your body use more sugar when you are active. Hypoglycemia is a reaction to too much insulin in your system. The insulin speeds up the lowering of the blood glucose level. Then without eating or with your body burning sugar faster because of physical activity, the level of sugar becomes dangerously low.

Several things can cause hypoglycemia. Your blood sugar level could be low if you:

  • Become more physically active than usual.
  • Miss a meal.
  • Change when or how much you normally eat.
  • Take your insulin or medication in a different amount or at a different time than usual.
  • Drink alcohol excessively without eating.


The symptoms of hypoglycemia can be classified as mild or early, moderate, and severe.

Mild Symptoms of Hypoglycemia

Mild symptoms include:

  • Dizziness
  • Irritability
  • Moodiness or sudden changes in behavior
  • Hunger
  • Shakiness
  • Sweating
  • Rapid heartbeat

Severe Symptoms of Hypoglycemia

When hypoglycemia becomes severe, symptoms may include:

  • Fainting and unconsciousness
  • Seizures
  • Coma
  • Confusion
  • Headache
  • Poor coordination

Nighttime Symptoms of Hypoglycemia

Hypoglycemia can also occur overnight while you sleep. Symptoms may include:

  • Crying out in your sleep
  • Nightmares
  • Damp pajamas or sheets resulting from perspiration
  • Waking up tired, irritable, or confused

If you experience any possible signs of mild hypoglycemia, it's important to check your blood sugar if you can to make sure it isn't low. If it is, you should treat it quickly or seek emergency care. However, if you notice symptoms and can't check your blood sugar level for some reason, you should go ahead and treat yourself for low blood sugar or seek emergency care. If symptoms are severe or you are unable to help yourself, seek emergency medical attention.

If your hypoglycemia is mild or moderate, the best way to raise your blood sugar level quickly is to eat or drink something that contains 15-20 grams of glucose or other sugar. You might take three to four glucose tablets or one-third to one-half tube of glucose in gel form, which you can buy at the drugstore. Or you may want to drink a half cup of fruit juice (orange juice or apple juice).

Other snacks you can use to raise your sugar level include:

  • 1/2 cup of regular soda (not diet soda)
  • 1 cup of milk
  • 1 tablespoon of sugar
  • 1 tablespoon of honey, molasses, or corn syrup
  • 1/4 cup raisins
  • 2 large or 6 small sugar cubes dissolved in water

You can also ask your doctor or dietitian for recommendations for other snack items that can help raise your blood sugar level when you need to.

After you've taken a snack, wait 15 minutes and check your blood sugar level again. If it is still low, eat another snack, then wait 15 minutes and check it again. Repeat the process until your blood sugar level is in its normal target range. Following that, eat another small snack if your regular meal is more than an hour away, such as half a sandwich, 1 ounce of cheese with 4-6 crackers, or 1 tablespoon of peanut butter with 4-6 crackers.

If you lose consciousness, you will need immediate medical attention. It's important that you educate the people in your family and the people you work with about insulin shock and about what to do if it happens. Someone should call 911 or arrange to get you to an emergency room if that's not possible. If you go to the hospital, doctors may give sugar through a vein (intravenously).

You can ask your doctor to prescribe a glucagon rescue kit and then teach others how to use it. Glucagon is a natural hormone that rapidly causes the level of sugar in your blood to rise. If you are unconscious, someone injecting you with glucagon even before emergency help arrives can prevent further complications and help you recover.