Glucagon Roles, Side Effects & How It Works With Insulin - Dr. Axe

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What Is Glucagon? Roles, Side Effects & How It Works With Insulin


Glucagon - Dr. Axe

We know that maintaining normal blood sugar levels is extremely important and can sometimes be challenging, but do you know how the body works to regulate this important function? A hormone called glucagon plays a major role.

Glucagon function kicks into action when your glucose levels become too low. It works with insulin to ensure that you maintain adequate blood glucose and can supply your body with fuel.

Unfortunately, these two important hormones don’t always work appropriately or can’t be produced at all. This can lead to major health issues if left unrectified.

What Is Glucagon? (Role in Body)

Glucagon is a peptide hormone that’s produced to maintain appropriate glucose levels in the bloodstream. Research indicates that it prevents blood glucose levels from becoming too low.

This is done through a process called glycogenolysis, which occurs when glucagon in the liver stimulates the conversion of stored glycogen to glucose. It’s this process that allows the body to maintain adequate plasma glucose concentrations.


Research suggests that glucagon is secreted from the alpha cells of the pancreas in response to:

  • hypoglycemia
  • long-term fasting
  • exercise
  • eating protein-rich meals

When you fast for a long period of time, this important protein promotes the use of stored fat for energy, which preserves the body’s use of glucose.

How It Works with Insulin

Glucagon and insulin are two hormones that work together to control blood sugar levels, but they have the opposite effects.

Glucagon is released when blood sugar levels become too low, while insulin is released when blood sugar levels are become too high.

In the case of hypoglycemia, the release of glucagon is stimulated in order to correct the imbalance. This may happen when a person has been fasting for a prolonged period of time or when he or she has eaten a meal containing high-protein foods.

Insulin, on the other hand, is stimulated during hyperglycemia, when blood sugar levels are too high.

Insulin signals your cells to take in glucose from the bloodstream to use it as energy. As the cells take in glucose, your blood glucose levels go down.

Any excess glucose is stored in the liver and muscles as a substance called glycogen. The body uses glycogen for energy in between meals.

Glucagon function promotes the conversion of glycogen to glucose when blood sugar levels become too low in order to keep this happy balance.

The body detects which hormone is needed to sustain blood sugar balance. Studies prove that glucagon release is prevented when blood glucose levels are elevated and after meals high in carbohydrates. On the flip side, the hormone is released after a meal high in protein.

Insulin plays a role in this balance as well — with its release triggered after high-carb meals and prevented after meals high in protein. The actions of glucagon and insulin goes back and forth throughout the day, regulating your blood glucose levels and body’s fuel supply.

Glucose Disorders

Abnormal glucose metabolism occurs when the body is unable to process sugar into energy. Humans need to maintain normal blood sugar levels in order to fuel the central nervous system.

The most common condition that hinders the body’s ability to maintain normal blood glucose is diabetes.

Insulin and glucagon aren’t produced or secreted properly for diabetics. This can lead to dangerously high blood glucose levels.

There are several types of diabetes that affect insulin and glucagon levels, including:


  • Type 1 diabetes: A less common form of diabetes in which the immune system destroys cells that make insulin, so the hormone is never produced and must be taken instead. Type 1 diabetes usually causes more severe diabetes symptoms, and symptoms usually develop sooner and at a younger age than type 2 diabetes.
  • Type 2 diabetes: This is when your body makes insulin, but your cells don’t respond to it properly. Type 2 diabetes leads to high blood glucose levels because insulin isn’t able to take it from the bloodstream for energy.
  • Prediabetes: Prediabetes symptoms occur when your blood glucose levels are above normal but below the defined threshold of diabetes. This is considered an “at risk state,” and it can usually be prevented with lifestyle and diet changes.
  • Gestational diabetes: Gestational diabetes is diagnosed between the 24th and 28th weeks of pregnancy and occurs when a pregnant woman’s blood sugar levels are too high.

The two situations that can occur when your insulin and glucagon hormones aren’t functioning properly are:

  • Hypoglycemia: Low blood glucose can happen as a result of fasting, excessive physical exertion and when diabetic patients unintentionally receive too much insulin or glucose-lowering medicine. Symptoms of hypoglycemia include:
    • hunger
    • anxiety and shakiness
    • sweating
    • dizziness
    • headache
    • muscle weakness
    • brain fog
  • Hyperglycemia: High blood glucose occurs when your body doesn’t make enough insulin or can’t use it properly. This occurs in diabetic patients and people with hormonal imbalances. Symptoms generally include:
    • increased thirst
    • frequent urination
    • trouble concentrating
    • blurred vision
    • headaches
    • weakness
    • numbness

Glucagon Injection Uses

Our bodies make glucagon naturally, but there is also a synthetic version that’s available as a prescription medication.

Glucagon injections are sometimes needed in severe cases of hypoglycemia. Injectable glucagon kits are available to patients with diabetes, in case they become unconscious from a severe insulin reaction, or to people with an unusual case of glucagon secretion deficiency.

An emergency kit typically contains freeze-dried glucagon in powder form, which can be used as an injection in a one-milliliter syringe of diluent. The powder contains one unit of glucagon, which is 1 milligram, and 49 milligrams of lactose. The unit is mixed with the diluent before injection.

The effect of a glucagon injection is limited. A person dealing with severe hypoglycemia would need to consume carbohydrates once he or she is able to do so in order to maintain blood sugar balance.


One unit of glucagon typically contains 1 milligram, which is the suggested dose for adults and children over 44 pounds with hypoglycemia. Children under 44 pounds should receive 0.5 units, which would be a 0.5 milligram dose of glucagon.

Another common dosage recommendation is 20–30 micrograms per one kilogram of body weight.

Glucagon units can be administered with an emergency kit intravenously, intramuscularly or subcutaneously.

After a hypoglycemic episode that requires glucagon administration, a health care professional should be notified, and glucose levels should be monitored until they are restored.

Risks, Side Effects and Interactions

Glucagon side effects may include nausea and vomiting. However, these are also symptoms of hypoglycemia for which synthetic glucagon may be used.

In rare cases, glucagon medications can cause allergy symptoms, such as rash, itching, respiratory issues and low blood pressure.

For people with conditions that won’t allow their livers to produce glucose properly, taking glucagon will not be effective. This may include patients with adrenal insufficiency and chronic hypoglycemia.

In these cases, oral glucose may be more effective.

It’s possible to secrete too much glucagon, which is caused by a rare tumor in the pancreas called a glucagonoma.

Excessive glucagon can cause health issues like:

  • diabetes mellitus
  • thrombosis
  • skin rash
  • weight loss

Glucagon does interact with certain medications, specifically anticoagulants like Warfarin. Patients who must take the hormone for low blood pressure while using anticoagulants should be monitored by a health care professional.

The safety of glucagon during pregnancy and while nursing is unclear, but the risk to the unborn fetus is considered low.


  • Glucagon is a peptide hormone that works together with insulin to maintain normal blood sugar levels.
  • This hormone is secreted when blood sugar levels become too low. It triggers the conversion of stored glycogen to glucose, which can then be used by the body for fuel.
  • For people with hypoglycemia, glucagon injections can be used to immediately regulate blood glucose. This is typically used for severe emergency situations.
  • The best way to resolve low blood sugar in normal situations is to eat a meal high in carbohydrates.

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