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FDA-approved

Digestive & weight

Glucagon

EvidenceFDA approved
ClassGlucagon receptor agonist

Glucagon is a pancreatic hormone that raises blood sugar fast. Learn its role in severe hypoglycemia, how nasal and injectable forms compare, and its status.

Reviewed by
William Maish, MD MBA MPH, Clinical Product Lead
Published
October 5, 2026
Last updated
October 5, 2026

Key takeaway

Glucagon (brands include Gvoke and the nasal powder Baqsimi) is a pancreatic hormone that raises blood sugar fast, used as emergency treatment for severe low blood sugar in people with diabetes. It signals the liver to release stored glucose. Glucagon products have long been FDA-approved in the U.S., and modern forms include ready-to-use injectors and a needle-free nasal powder.

At a glance

What it isA pancreatic peptide hormone that raises blood glucose (counter-regulatory to insulin)
Approved forSevere hypoglycemia in diabetes; also a diagnostic aid to relax the gastrointestinal tract during imaging
Key factA single nasal dose raises blood glucose comparably to injected glucagon in adults with type 1 diabetes
RouteSubcutaneous, intramuscular, or intravenous injection, or nasal powder
Evidence strengthFDA approved

What is glucagon?

Glucagon is a 29-amino-acid hormone made by the pancreas that works opposite to insulin: when blood sugar drops, glucagon raises it. As a medicine it is the emergency rescue treatment for severe hypoglycemia, the dangerous low-blood-sugar episodes that can occur in people with diabetes, especially those on insulin. It is sold as the ready-to-use Gvoke injector and Baqsimi, a nasal powder, among other products. The GlucaGen HypoKit emergency kit was discontinued1 in the U.S. in 2024.

How does glucagon work?

Glucagon binds glucagon receptors on liver cells and switches on the pathways that release glucose. It stimulates glycogenolysis, the breakdown of stored glycogen into glucose, and gluconeogenesis, the making of new glucose, so the liver pushes glucose into the bloodstream and blood sugar rises within minutes. This is why it works as a rescue treatment when someone with hypoglycemia is unable to eat or drink.

Because the effect depends on the liver having glucose stores to release, glucagon can be less effective when those stores are depleted, such as in prolonged fasting or starvation. Glucagon also relaxes the smooth muscle of the gastrointestinal tract, which is the basis of its separate use as a diagnostic aid during certain imaging studies. In a trial in adults with type 1 diabetes, a nasal powder formulation raised blood glucose2 about as effectively as injected glucagon, with the practical advantage of needing no injection or mixing in an emergency.

Is it FDA-approved?

Yes. Glucagon is approved for severe hypoglycemia and as a diagnostic aid for gastrointestinal imaging. The table shows when each product was approved:

ProductTypeFDA approval
Glucagon for injection, including the recombinant GlucaGenInjectionApproved for decades
Gvoke3Newer ready-to-use injector2019
Baqsimi4Newer ready-to-use nasal powder2019

What is glucagon prescribed for?

Glucagon is prescribed as emergency treatment for severe hypoglycemia in people with diabetes, typically given by a caregiver when the person cannot safely take sugar by mouth. Injectable forms are also used to relax the gut during radiologic procedures. It is contraindicated in pheochromocytoma (a catecholamine-producing tumor) and in insulinoma.

What are the side effects?

According to the injectable3 and nasal powder4 labels, common side effects include:

  • Nausea and vomiting
  • Headache
  • Injection-site reactions, or nasal and eye symptoms with the nasal powder

More serious considerations include:

  • A sharp rise in blood pressure in people with pheochromocytoma
  • Low blood sugar rebound in people with insulinoma
  • Rare allergic reactions

More for digestive & weight

Sources: FDA prescribing information for GlucaGen, Gvoke, and Baqsimi; a randomized trial of nasal glucagon in adults with type 1 diabetes (Rickels et al., Diabetes Care, 2016, DOI: 10.2337/dc15-14982), indexed on PubMed. This document is educational and does not constitute medical advice.