Glucagon
Insulin's opposite number, now sold as a nasal powder and a ready-filled pen because the old kit had to be mixed in an emergency
Glucagon raises blood sugar by telling the liver to release it. For decades the only emergency form was a powder needing reconstitution by whoever was present, often during a seizure. The newer products — a nasal powder and prefilled autoinjectors — exist to remove that step.
What is it?
The pancreas has two answers to blood sugar. Beta cells release insulin when it rises; alpha cells release glucagon when it falls, and the liver answers by breaking down glycogen and making new glucose. That makes glucagon the natural rescue for severe hypoglycaemia, the emergency in which someone with diabetes cannot treat themselves.
The problem was never the hormone but the vial. Native glucagon is barely soluble and unstable in water, so emergency kits shipped as a powder and a syringe of diluent to be mixed by a bystander during a seizure. That is the delivery problem the current products solve: Baqsimi is a 3 mg nasal powder for anyone aged 1 and over, and Gvoke is a ready-filled subcutaneous pen for anyone aged 2 and over.
The nasal powder was tested where it matters. In a crossover trial in adults with type 1 diabetes whose blood sugar had been driven down to about 48 mg/dL with insulin, 3 mg of intranasal glucagon succeeded at 98.7% of visits against 100% for a 1 mg intramuscular injection, meeting the non-inferiority margin; recovery took 16 minutes against 13. Head and facial discomfort was more common with the nasal dose (25% against 9% of visits), and nausea was similar (35% against 38%). In 48 children and teenagers aged 4 to under 17, 58 of 59 nasal doses and all 24 intramuscular doses raised glucose by at least 25 mg/dL, and a single 3 mg nasal dose was judged suitable across the whole age range.
Both new products are simple by label. Baqsimi is one 3 mg puff into one nostril, which does not need to be inhaled; it peaks in about 15 minutes and has a median half-life of about 35 minutes. Gvoke is 1 mg under the skin from age 12, or 0.5 mg for children aged 2 to under 12 who weigh less than 45 kg; it peaks about 50 minutes after injection with a half-life of 32 minutes. With either, the label says to call emergency help straight away, give a second dose from a new device if there is no response after 15 minutes, and give carbohydrate by mouth once the person can swallow.
A chemical answer exists too. Dasiglucagon is an analogue stable in solution, and in 58 people with type 1 diabetes it raised plasma glucose as quickly as GlucaGen from induced hypoglycaemia — above 70 mg/dL within 6 to 10 minutes — with a longer-lasting effect. A dedicated immunogenicity trial in 112 people found no anti-drug antibodies at all across three weekly doses.
Glucagon's other role is as a diagnostic aid and, increasingly, as half of a drug: its receptor is one of the targets in the dual and triple agonists now in late-stage obesity trials. A 2025 study in nine people with no pancreas used a receptor antagonist to test whether glucagon from outside the pancreas still does anything measurable.
The labels share a set of warnings that follow from what glucagon does. It is contraindicated in phaeochromocytoma, because it can release catecholamines from the tumour, and in insulinoma, where it can provoke a later hypoglycaemia. It may not work in people with little stored liver glycogen, such as in starvation, adrenal insufficiency or chronic hypoglycaemia, because it works by releasing that store. Serious allergic reactions have been reported, and the Gvoke label also lists necrolytic migratory erythema, a rash reported after continuous glucagon infusion, a use Gvoke is not approved for.
Mechanism of Action
Glucagon binds glucagon receptors in the liver, which then breaks down stored glycogen and makes new glucose, raising blood sugar within minutes.
Liver glucose release
It drives the liver to release glucose from glycogen, which is why it reverses severe hypoglycaemia and why it may fail when glycogen stores are empty (labels).
The counterweight to insulin
Alpha cells release it when blood sugar falls; in type 1 diabetes that response is impaired, so an outside dose stands in for it.
Gut relaxation
Given intravenously it temporarily stops gut movement, its use as a diagnostic aid in radiology (Gvoke VialDx).
Catecholamine release
It can release catecholamines from a phaeochromocytoma and raise blood pressure sharply, the reason that tumour is a contraindication.
Published Research
The studies behind glucagon, read from their PubMed abstracts: the nasal powder in adults and children, the stable analogue dasiglucagon, and the delivery problem.
Nasal against intramuscular glucagon, adults
In a randomised crossover trial in adults with type 1 diabetes after insulin-induced hypoglycaemia (glucose about 48 mg/dL), 3 mg intranasal glucagon succeeded at 98.7% of visits against 100% for 1 mg intramuscular, meeting non-inferiority; time to success was 16 against 13 minutes.
Nasal glucagon in 48 children and teenagers
Participants aged 4 to under 17 received 2 or 3 mg intranasal or weight-based intramuscular glucagon after glucose was lowered below 80 mg/dL; 58 of 59 nasal and all 24 intramuscular doses raised glucose by at least 25 mg/dL, and 3 mg was judged suitable for all ages.
A stable analogue against the old kit
58 people with type 1 diabetes received 0.1 to 1.0 mg of dasiglucagon or 0.5 or 1.0 mg of GlucaGen during insulin-induced hypoglycaemia. Both raised glucose above 70 mg/dL within 6 to 10 minutes; dasiglucagon peaked at about 35 minutes with a half-life near half an hour and lasted longer.
Whether the analogue provokes antibodies
112 people with type 1 diabetes took three weekly subcutaneous doses of 0.6 mg dasiglucagon or 1.0 mg recombinant glucagon and were followed 15 weeks. No participant developed any treatment-induced or boosted anti-drug antibody, and no injection-site reactions were reported on dasiglucagon.
Why the delivery changed
A review of glucagon delivery: the nasal powder and the ready-to-use autoinjector pens against the traditional kits that must be mixed at the moment of use, and the formulation problems — stability, bioavailability, onset — each approach still carries.
Dosing Data
Glucagon for severe hypoglycaemia is given once by a bystander: a 3 mg nasal puff or a subcutaneous injection, repeated once after 15 minutes if there is no response.
Educational information, not medical advice. Each dose above is tagged with its source: an approved label, a published human study, animal data, or amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.
Side Effects & Contraindications
Reported Side Effects
From the trials above, the Baqsimi prescribing information (DailyMed set 32ba41fa, version 1, effective June 19, 2026) and the Gvoke prescribing information (DailyMed set 359982a8, version 2, effective July 7, 2026).
Contraindications & Cautions
Set by the labels of the individual products.
Legal Status
Glucagon is approved in the US in several forms.
Frequently Asked Questions
?What does glucagon do?
It tells the liver to release stored glucose and make new glucose — the pancreas's counterweight to insulin.
?What is it used for?
Severe hypoglycaemia a person with diabetes cannot treat themselves, and as a diagnostic aid in gut procedures.
?Why are there nasal and pen versions?
The old kit had to be mixed by a bystander during an emergency; the nasal powder and prefilled pens remove that step.
?Can it fail?
Yes. It releases stored liver glycogen, so it may fail in starvation, adrenal insufficiency or prolonged hypoglycaemia.
?Does the nasal spray work as well as an injection?
In adults it reversed insulin-induced hypoglycaemia at 98.7% of visits against 100% for an intramuscular injection, a few minutes more slowly (16 against 13 minutes).
?What dose is used?
Baqsimi is 3 mg in one nostril from age 1. Gvoke is 1 mg under the skin from age 12, and for children aged 2 to under 12, 0.5 mg if they weigh under 45 kg or 1 mg if 45 kg or more.
?What if it does not work?
The labels say to call emergency help straight away, give a second dose from a new device after 15 minutes without a response, and give carbohydrate by mouth once the person responds.
?Who should not use it?
People with phaeochromocytoma or insulinoma, and it may not work where liver glycogen is depleted, such as in starvation or adrenal insufficiency.
References
- [fda-pi] Baqsimi (glucagon) nasal powder Prescribing Information, sections 1 and 2 (DailyMed version 1, effective June 19, 2026; read September 30, 2026).
- [fda-pi] Gvoke (glucagon) injection Prescribing Information, sections 1 and 2 (DailyMed version 2, effective July 7, 2026; read September 30, 2026).
- [pubmed] Rickels MR, et al. "Intranasal Glucagon for Treatment of Insulin-Induced Hypoglycemia in Adults With Type 1 Diabetes: A Randomized Crossover Noninferiority Study." Diabetes Care, 2016;39(2):264-70. PMID: 26681725.
- [pubmed] Sherr JL, et al. "Glucagon Nasal Powder: A Promising Alternative to Intramuscular Glucagon in Youth With Type 1 Diabetes." Diabetes Care, 2016;39(4):555-62. PMID: 26884472.
- [pubmed] Hövelmann U, et al. "Pharmacokinetic and Pharmacodynamic Characteristics of Dasiglucagon, a Novel Soluble and Stable Glucagon Analog." Diabetes Care, 2018;41(3):531-537. PMID: 29273578.
- [pubmed] Pieber TR, et al. "Immunogenicity of the Novel Glucagon Analogue Dasiglucagon: Results of a Dedicated Immunogenicity Trial in Type 1 Diabetes." Diabetes Technol Ther, 2021;23(11):773-776. PMID: 34252289.
- [pubmed] Kumar S, et al. "Glucagon: Delivery advancements for hypoglycemia management." Int J Pharm, 2024;652:123785. PMID: 38224759.
- [pubmed] Kronfol MM, et al. "Clinical Pharmacology of Glucagon." Clin Pharmacol Ther, 2024;116(4):976-979. PMID: 38847591.
- [pubmed] Juel CT, et al. "Using glucagon receptor antagonism to evaluate the physiological effects of extrapancreatic glucagon in totally pancreatectomised individuals: a randomised controlled trial." Diabetologia, 2025;68(12):2807-2822. PMID: 40968190.
- [other] US FDA, Drugs@FDA (openFDA): GLUCAGEN, NDA 020918, Discontinued; generic glucagon kits marketed under NDA 201849 and ANDAs 204468, 208086, 214457 and 218813. Read September 30, 2026.
Sources & Citations
Studies were read from their PubMed records (October 5, 2026); the labels and Drugs@FDA are listed below with their read dates.
Medical Disclaimer: This content is for educational and informational purposes only. It is not medical advice, and nothing here is an instruction to obtain or use any compound. Talk to a licensed clinician about your own situation.