At a glance
| Physiology | Pancreatic alpha-cell hormone |
|---|---|
| Rescue role | Severe hypoglycemia |
| Routes | Product-specific injectable or intranasal |
| Other role | Selected diagnostic procedures |
| Limitation | Reduced effect with depleted glycogen |
Overview
The body releases glucagon from pancreatic alpha cells to help maintain blood glucose during fasting. Pharmaceutical glucagon turns that physiology into an emergency treatment for severe low glucose, especially when a person cannot safely swallow. Approved products include traditional injection kits and ready-to-use injectable or nasal formulations. Some injectable labeling also covers temporary inhibition of gastrointestinal movement during diagnostic examinations. These are distinct indications: a diagnostic product or device should not be assumed equivalent to a particular home rescue product merely because it contains glucagon.
How it works
Glucagon activates a G-protein-coupled receptor that increases intracellular cyclic AMP, especially in the liver. This promotes glycogen breakdown and glucose release. Its gastrointestinal smooth-muscle effects support selected diagnostic uses. A rescue response can be inadequate after prolonged fasting or in other conditions with depleted liver glycogen, so the hormone is not a universal solution for every cause of low glucose.
Rescue and diagnostic indications
Baqsimi is a nasal glucagon rescue product, while GlucaGen and other injectable products have their own indications and age instructions. Gastrointestinal diagnostic use belongs to particular injectable labels and should not be generalized to every glucagon formulation.
Evidence for nasal delivery
A randomized crossover study in adults with type 1 diabetes compared nasal and intramuscular glucagon during induced hypoglycemia. Both achieved the study’s recovery criteria in nearly all administrations. This supports nasal delivery without requiring the person to inhale deliberately.
Supporting sources [3]
Known adverse effects
Nausea and vomiting are common across rescue formulations; nasal products can cause nasal or eye irritation. Serious allergy can occur. Pheochromocytoma and insulinoma are important contraindications because glucagon can provoke dangerous hormonal responses in these conditions.
The glycogen limitation
Prolonged fasting, starvation, adrenal insufficiency and chronic hypoglycemia may leave inadequate hepatic glycogen for a useful response. A severe episode remains an emergency even if a rescue product has been given, and recurrent episodes require investigation of the underlying cause.
Why product training matters
An injectable kit requiring preparation, a ready-to-use device and a nasal dispenser involve different actions under stress. A household rescue plan should correspond to the prescribed product and the people likely to assist, rather than relying on generic instructions for glucagon.
Reading this profile
Jurisdiction: United States — FDA-approved prescription medicine; indication and formulation restrictions apply.. Molecular class: Pancreatic peptide hormone and pharmaceutical rescue hormone.
This profile was written with AI-assisted research and checked against the linked sources. It has not been represented as a clinician’s review. Evidence summaries describe the cited studies and products; they do not establish that a separately purchased preparation is equivalent.
Sources & references
Follow the original material. Product labels define specific formulations and uses; trial registration describes a study and does not by itself establish benefit.
- FDA: Baqsimi prescribing information ↗Regulatory source · Checked 2026-10-27
- DailyMed: GlucaGen current prescribing information ↗Regulatory source · Checked 2026-10-27
- Intranasal Glucagon for Treatment of Insulin-Induced Hypoglycemia in Adults With Type 1 Diabetes: A Randomized Crossover Noninferiority Study. ↗Original research · Checked 2026-10-27