What Does Glucagon Do?

Glucagon is a hormone your pancreas makes that raises blood sugar when it drops too low. Think of it as the emergency rescue team for low blood glucose. While insulin lowers blood sugar, glucagon does the opposite — it signals the liver to release stored sugar into the bloodstream.

How Does Glucagon Work in the Body?

Glucagon acts mainly on the liver. When your blood sugar falls below normal, the alpha cells in your pancreas release glucagon. This hormone then travels to the liver and tells it to break down stored glycogen into glucose. That glucose then enters your blood, bringing sugar levels back up.

It also signals the liver to make new glucose from other sources like amino acids. This process is called gluconeogenesis. Between meals, during sleep, or after intense exercise, glucagon keeps your blood sugar from dropping too low.

The balance between insulin and glucagon is what keeps your blood sugar stable throughout the day. When that balance breaks, problems like diabetes can develop.

What Is the Glucagon Emergency Kit Used For?

A glucagon emergency kit is a prescription medicine for severe hypoglycemia — dangerously low blood sugar. This happens when a person with diabetes cannot swallow or is unconscious. In those moments, glucagon given as an injection or nasal spray can raise blood sugar within minutes.

The American Diabetes Association recommends that anyone taking insulin should have a glucagon kit available. Family members and coworkers should know how to use it. The kit contains a powder and a liquid that you mix and inject, or a ready-to-use nasal powder.

It is not for mild low blood sugar that you can treat with juice or glucose tablets. It is only for emergencies where the person cannot take anything by mouth safely.

What Does Glucagon Do for People Without Diabetes?

In people without diabetes, glucagon works the same way — it raises blood sugar when needed. But their bodies naturally regulate it. The pancreas releases glucagon in response to low blood sugar and stops when levels are normal.

Some research has looked at glucagon for weight loss. The idea is that it might speed up metabolism or reduce appetite. Evidence is limited. A small study published in the Journal of Clinical Endocrinology & Metabolism found that glucagon combined with another hormone reduced food intake in some people. But this is not a proven or approved treatment for weight loss.

There is no clinical evidence that taking extra glucagon improves health or performance in people with normal blood sugar regulation. Your body already makes what it needs.

What Are the Side Effects of Glucagon?

Glucagon given as a medicine can cause side effects. The most common are nausea and vomiting. Some people also get a headache or feel dizzy. These effects usually go away quickly.

More serious but rare side effects include allergic reactions, low blood pressure, or irregular heart rhythm. If someone vomits after receiving glucagon, turn them on their side so they do not choke.

The nasal powder form may cause temporary irritation in the nose or eyes. It can also cause a runny nose or watery eyes. These effects are mild and short-lived.

For people with certain medical conditions like a tumor in the pancreas called a glucagonoma, glucagon can be dangerous. Your doctor will check your health history before prescribing it.

What Does Research on Glucagon Show?

Research on glucagon goes back decades. The first study showing its blood sugar-raising effect was published in the 1920s. Modern research has focused on improving emergency treatments and understanding its role in metabolism.

A 2015 study in the New England Journal of Medicine compared nasal glucagon with injectable glucagon for severe hypoglycemia. Both worked equally well. The nasal form was easier for untrained people to use. This led to FDA approval of the nasal spray in 2019.

Some studies suggest glucagon might help with type 1 diabetes management through dual-hormone artificial pancreas systems. These systems deliver both insulin and glucagon automatically. Early results are promising but not yet standard care.

Research published in Diabetes Care in 2021 found that glucagon can also affect how the body uses fat for energy. This is an area of active study, but no practical applications exist yet.

What Are Common Misconceptions About Glucagon?

One big myth is that glucagon is the same as insulin. They are opposites. Insulin lowers blood sugar. Glucagon raises it. Both come from the pancreas, but they do different jobs.

Another misconception is that you can use glucagon for mild low blood sugar. You cannot. It is only for emergencies when the person cannot swallow or is unconscious. Using it when not needed can cause dangerously high blood sugar.

Some people think glucagon is a weight loss drug. It is not. While some research has looked at its effects on appetite, it is not approved or safe for that use. Taking it without a medical reason can cause harm.

Finally, some believe that glucagon only works for people with diabetes. That is false. Everyone makes glucagon. It is a normal part of how your body regulates blood sugar. The emergency kit is just for people who cannot make enough or need extra help during severe lows.

Glucagon vs. Insulin: Key Differences

When Should Someone Use a Glucagon Kit?

Use a glucagon kit only when a person with diabetes has severe low blood sugar and cannot take sugar by mouth. Signs include confusion, inability to wake up, seizures, or unconsciousness. Do not give anything by mouth to someone who is not fully awake — they could choke.

Call 911 right after giving glucagon. The person needs medical follow-up even if they wake up. Blood sugar can drop again.

If you are not sure whether to use it, err on the side of caution. Giving glucagon when blood sugar is not extremely low is safer than not giving it when it is. The main risk is vomiting, not lasting harm.

People with diabetes should check their glucagon kit expiration dates regularly. The medicine loses effectiveness over time. Replace it before it expires.

How Is Glucagon Given?

Glucagon comes in two main forms: injectable and nasal. The injectable form requires mixing a powder with a liquid in a syringe. You inject it into the upper arm, thigh, or buttock. The nasal form is a single-use device you spray into one nostril.

Both work within 5 to 15 minutes. The person should wake up and be able to eat or drink something with sugar soon after. If they do not respond within 15 minutes, a second dose may be needed, but medical help should already be on the way.

Family members and caregivers should practice with a training kit. These kits contain saline instead of glucagon so you can learn without wasting real medicine. Your diabetes care team can show you how.