Glucagon raises blood glucose by signaling the liver to release stored glycogen.

What is the primary action of glucagon?

• A. Decreases blood glucose by blocking sugar release
• B. Increases blood glucose by stimulating liver to release stored glycogen
• C. Stimulates insulin production in the pancreas
• D. Inhibits glycogen breakdown

Answer: (B)

The primary action of glucagon is to increase blood glucose levels, and it does this by stimulating the liver to release stored glycogen. Glycogen is a polysaccharide that serves as a form of glucose storage in the liver. When blood glucose levels drop, such as in instances of hypoglycemia, glucagon is secreted from the alpha cells of the pancreas. This hormone binds to receptors in the liver, promoting the conversion of glycogen back into glucose, allowing it to enter the bloodstream and raise blood glucose levels. This function is crucial in maintaining homeostasis, particularly during fasting or when the body experiences low sugar levels. By increasing blood glucose, glucagon helps ensure that the body, especially the brain, receives enough energy to function properly. Other options describe actions that do not accurately reflect glucagon's role. For instance, glucagon does not decrease blood glucose levels or stimulate insulin production; rather, it has the opposite effect and is released in situations where blood sugar needs to be elevated.

Imagine rolling up to a home call where a person is sweaty, confused, and trying to tell you their blood sugar is "low." The room feels warmer than it should, and every second counts. In that moment, a tiny but mighty hormone does the heavy lifting: glucagon. But what does it actually do, and why does it matter for EMTs when every minute matters?

What glucagon actually does (the core action)

Here’s the core truth in plain terms: glucagon increases blood glucose by signaling the liver to release stored glycogen. It’s not about lowering sugar or dialing up insulin. It’s a hormone that kicks into gear when your blood sugar dips, especially during fasting or when someone can’t swallow or keep food down.

If you’re thinking, “But isn’t insulin the big player here?”—glucagon is the opposite of insulin’s job. Insulin lowers blood glucose by promoting uptake into cells and storage, while glucagon does the exact opposite: it mobilizes glucose from stores to raise the level in the bloodstream. In the EMS world, that difference matters a lot, because when a patient has a severe hypoglycemia episode, we need to get glucose back into the brain fast. Glucagon is one reliable way to jump-start that rescue, especially when IV access isn’t available.

How it works in the body (the quick science, made simple)

Let me explain the chain of events you’re looking for in a patient’s chart or in the field notes:

• The trigger: Blood glucose drops. The pancreas senses this and releases glucagon from alpha cells.

• The signal: Glucagon travels to the liver and binds to its receptors. This sets off a cascade inside liver cells.

• The reaction: The liver starts glycogenolysis—breaking down stored glycogen into glucose, which spills into the bloodstream. In practical terms, glucose is released where it’s most needed: back into the blood and to the brain.

• A backup plan: If glucose stores are really low or the liver’s glycogen is depleted, glucagon can support gluconeogenesis to generate glucose from amino acids, though this is a slower route.

• The result: Blood sugar rises, which helps restore brain function, improves mental status, and buys time for definitive care.

A few real-world caveats

• It isn’t a magic reset button. If a patient has very little glycogen stored (think long fasting, extreme malnutrition, or liver disease), the glucose rise may be modest.

• It won’t work instantly the way an IV bolus of dextrose would. Onset is often 10 to 15 minutes after administration, which is why IV access remains the preferred route when available. Still, glucagon shines when IVs aren’t in play.

• It doesn’t trigger insulin. That might sound like a silly point, but it’s important: glucagon’s job is to raise glucose, not to stimulate insulin release. In some patients, the balance of hormones will influence the overall response.

When EMTs reach for glucagon (useful, practical context)

You’ll most likely see glucagon used in two common EMS scenarios:

• Unresponsive or unable-to-swallow patients with suspected hypoglycemia. If a patient can’t protect their airway or swallow safely, glucagon—delivered by intramuscular injection—can rapidly raise blood glucose without needing IV access.

• Situations where IV dextrose isn’t immediately possible. In the field, time matters. If you can’t establish IV access quickly, a glucagon dose can be a lifesaver to stabilize the situation while you set up IV access or arrange rapid transport.

Glucagon dosing at a glance

• Adults: typically 1 mg given IM (intramuscular) for hypoglycemia when IV access isn’t available.

• Children: dosing can be weight-based, commonly around 0.5 mg IM for those who weigh under a certain threshold, but protocols can vary, so follow your agency’s guidelines.

• Brand and fulfillment: GlucaGen is a well-known option used in many EMS settings. kits may be ready-to-use or require reconstitution, so check your equipment and expiration dates regularly.

A quick note on the kit and the moment of truth

Glucagon kits are designed to be straightforward under pressure. The goal is to deliver the medicine safely, quickly, and with minimal confusion. In the middle of a tense call, you don’t want to be fumbling with complicated steps. The generic idea is: verify patient, confirm no allergy or contraindication, administer IM, monitor patient, and prepare for transport. After you inject, keep the patient on monitor, check their blood glucose if you have a handheld glucometer, and be prepared to support airway and breathing as needed.

Myths and missteps to avoid (the practical eye-openers)

• Myth: Glucagon fixes every case of low blood sugar. Reality: It helps when there’s some glycogen to mobilize. If the liver’s stores are depleted, its effect is limited.

• Myth: It works as fast as IV dextrose. Reality: The onset is slower than IV glucose, so don’t rely on it to rescue a comatose patient immediately if you have IV access.

• Mistake: Administering glucagon when it’s not indicated. If the patient can swallow safely and can take oral carbs, IV dextrose or oral glucose might work faster. Glucagon is most useful when the airway is at risk or IV access isn’t ready.

• Mistake: Not monitoring after administration. The moment glucagon goes in, you should monitor mental status, airway, breathing, and blood glucose, because the situation can evolve.

Connecting the dots: why this matters in EMS and beyond

Glucagon’s role isn’t just a neat fact on a test sheet. It’s a real-world tool that helps EMTs in the field bridge a dangerous chasm—between a slipping glucose level and a patient who can wake up and orient themselves. It’s part of a broader safety net you carry: a plan for hypoglycemia that includes quick assessment, airway management, and rapid transport when glucose fails to rise quickly enough.

Think of it like a relay race. The driver hands the baton (glucagon) to the liver, the liver hands glucose back into the bloodstream, and the brain gets the fuel it needs to function, while you call for backup or escalate care. It’s teamwork, chemistry, and good judgment all in one.

Practical tips you can carry into the field

• Know your protocol. Glucagon dosing and indications vary by jurisdiction and agency. Familiarize yourself with the exact steps you’re trained to follow, including when to use it versus other glucose-raising methods.

• Check your stock. Glucagon kits have expiration dates and storage requirements. A stale kit is a non-starter in an emergency.

• Keep it accessible. In a chaotic scene, you don’t want to hunt for the kit. Store it with your other airway and IV supplies so you can grab it in a heartbeat.

• Don’t skip the follow-up. After glucagon, monitor glucose and mental status. If there’s still confusion or a drop in vitals, treat accordingly and transport promptly.

• Communicate clearly. Let the patient (if conscious) know what you’re giving and why. If the patient regains consciousness, a simple explanation helps them understand what’s happening and can reduce fear or resistance to care.

A closing thought: the bigger picture

Glucagon is a reminder that the human body has built-in redundancies—systems that can rally when one part falters. For EMTs, understanding not just the what, but the why, makes a difference. When you know glucagon’s action—the liver’s glycogen stores being tapped to steady the line—you approach each call with a blend of technical precision and calm assurance. You’re not just saving a moment; you’re preserving a person’s ability to think clearly, to connect with loved ones, to keep moving forward after a difficult night.

If you ever wonder how a single hormone fits into the whole emergency response puzzle, here’s the bottom line: glucagon’s primary action is to raise blood glucose by signaling the liver to release stored glycogen. It’s a focused, practical tool—one that, when used appropriately, can avert a crisis and keep a patient’s brain alive long enough to get safer care.

Final takeaway

• Primary action: Increases blood glucose by stimulating liver to release stored glycogen.

• Key mechanism: Glucagon binds liver receptors, triggers glycogenolysis, and raises glucose in the bloodstream.

• Field reality: Useful when IV access isn’t immediately available or when a patient is unable to protect their airway and swallow.

• The mindset: Be precise, stay monitor-ready, and know when to switch to other glucose-elevating strategies if needed.

In the end, it’s about staying prepared, staying calm, and using the right tools at the right moment. Glucagon is one of those tools that, when understood and used well, can make a life-or-death difference on a quiet street or a busy shift—time, after all, is the enemy in any hypoglycemic crisis.