Glucagon Agents
High-yield Verified · Oct 2026Glucagon Agents are a class of medications used for severe hypoglycemia in people with diabetes.
Medical view → mechanisms, drug comparisons and Step 1 pharmacology
When a person with diabetes is too low to swallow, someone else gives glucagon — an injection or a puff of nasal powder — calls for emergency help, and feeds the person once they wake.
How it works in the body
The system involved, what goes wrong, and how the drug and body interact.
01 Glucose from the liver’s glycogen
Glucagon activates hepatic glucagon receptors, which stimulates glycogen breakdown and the release of glucose from the liver. Its receptor is a G protein–coupled receptor that activates adenylate cyclase and raises cAMP, driving glycogenolysis and gluconeogenesis. After an injection, blood glucose begins to rise within about 10 minutes and peaks at around 30 minutes.
Because it works through the liver, glucagon is effective only when there is enough hepatic glycogen. In starvation, adrenal insufficiency or chronic hypoglycemia the stores may be too low, and those patients are treated with glucose instead. Dasiglucagon, a glucagon analog, is a glucagon receptor agonist with the same hepatic action and the same need for glycogen. Glucagon also relaxes the smooth muscle of the stomach, duodenum, small bowel and colon, which is why it is used to stop gut movement during radiologic examinations.
02 Rescue, then sugar, then help
Severe hypoglycemia needs someone else to treat it, so patients tell the people around them about their glucagon and its instructions. A person with a decreased level of consciousness cannot safely take oral sugar because of the risk of aspiration, and IV access can be hard to obtain, so glucagon is given as soon as severe hypoglycemia is recognized. Gvoke is injected subcutaneously from a prefilled autoinjector, syringe or kit; Baqsimi is a nasal powder sprayed into one nostril, which does not need to be inhaled and still works during a cold with nasal congestion. Generic kits are reconstituted before injection. Zegalogue (dasiglucagon) is a solution injected subcutaneously from a single-dose autoinjector or prefilled syringe.
After the dose, the rescuer calls for emergency help. If there is no response after 15 minutes, a second dose from a new device may be given while help is on the way. Because vomiting is common, an unconscious patient is turned on their side to prevent choking. Once awake and able to swallow, the patient is given oral carbohydrate to restore liver glycogen and prevent the low from coming back.
Drug names
* Zegalogue (dasiglucagon): Drugs@FDA lists Zegalogue as discontinued, although Novo Nordisk’s Zegalogue label is current with active NDCs (2026).
Indications
- Severe hypoglycemia in people with diabetes — glucagon injection (Gvoke, from age 2; generic kits), glucagon nasal powder (Baqsimi, from age 1) or dasiglucagon injection (Zegalogue, from age 6)
- Diagnostic aid in radiologic examinations — IV glucagon to temporarily inhibit movement of the gastrointestinal tract in adults
Mechanism of action
Glucagon activates hepatic glucagon receptors — G protein–coupled receptors that raise cAMP — stimulating glycogenolysis and gluconeogenesis so the liver releases glucose; hepatic glycogen stores are needed for the effect. Outside the liver it relaxes gastrointestinal smooth muscle. Dasiglucagon, a glucagon analog, is a glucagon receptor agonist with the same hepatic action and the same need for glycogen.
Therapeutic effects — what you'll see working
Success is a patient who wakes up and can swallow, with blood glucose rising within minutes — then eats carbohydrate so the low does not return.
- ↑ Blood glucose
- Blood glucose starts to rise within about 10 minutes of an injection and peaks at around 30 minutes; the effect lasts 60–90 minutes after IV or IM injection, so oral carbohydrate follows once the patient can swallow.
- GI smooth-muscle relaxation (diagnostic use)
- Relaxation of the stomach, duodenum, small bowel and colon temporarily stops gut movement during radiologic examinations.
Adverse effects
Most effects are short-lived: nausea and vomiting are the commonest, and the nasal powder irritates the nose and eyes. The serious risks are hormone release from a pheochromocytoma or insulinoma, and allergic reactions.
Interactions
Contraindications
The contraindications guard against hormone release from a pheochromocytoma or insulinoma, and against allergy.
When to hold
Assess before giving — these findings mean hold the dose and act.
Labs & levels
Nursing considerations
The RN-specific layer — each action paired with the reason it matters.
Common questions
What are Glucagon Agents used for?
How do Glucagon Agents work?
What are the serious side effects of Glucagon Agents?
When should a nurse hold Glucagon Agents, and what safety checks apply?
What labs should be monitored with Glucagon Agents?
See also
Replace or supplement the body’s own insulin to lower blood glucose. High-alert — hypoglycemia is the #1 risk.
Non-insulin agents for type 2 diabetes — each subclass targets a different broken "lever." Metformin is first-line.
Four smaller groups of type 2 diabetes drugs, each with its own lever: pioglitazone sensitizes tissues to insulin, acarbose and miglitol slow carbohydrate digestion in the gut, repaglinide and nateglinide give a short burst of insulin at meals, and pramlintide adds amylin alongside mealtime insulin. Their signature risks follow the lever: fluid retention and heart failure, gas and diarrhea, hypoglycemia with skipped meals, and severe hypoglycemia with insulin.
Replace thyroid hormone in hypothyroidism, or block its synthesis — or destroy the gland with radioactive iodine — in hyperthyroidism. TSH is the monitoring dial.
Powerful anti-inflammatory/immunosuppressive hormones. Never stop abruptly after prolonged use — taper.
Fludrocortisone replaces the missing mineralocorticoid in primary adrenal insufficiency, so it retains sodium and loses potassium — watch blood pressure, swelling and potassium. Osilodrostat and metyrapone block the last step of cortisol synthesis, and mifepristone (Korlym) blocks cortisol at its receptor; all three can tip a patient into adrenal insufficiency.
Sources
- GVOKE (glucagon injection) — severe hypoglycemia, administration, warnings (FDA label) — FDA / DailyMed
- BAQSIMI (glucagon nasal powder) — administration, adverse reactions, nasal congestion (FDA label) — FDA / DailyMed
- ZEGALOGUE (dasiglucagon injection) — severe hypoglycemia, administration, warnings, adverse reactions (FDA label) — FDA / DailyMed
- Glucagon for Injection kit (Fresenius Kabi) — indications, contraindications, warnings, interactions, pharmacodynamics (FDA label) — FDA / DailyMed
- Glucagon — mechanism, rescue without IV access, adverse effects — StatPearls (NCBI)
Reviewed by Hae Suk Lee, RN
Educational summary for nursing students. Always verify against current prescribing information and your institution's protocols before administering. Not medical advice.