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OTHERPEPTIDE PROFILE

Glucagon

Also known as GlucaGen, glucagon rDNA origin, glucagon HCl

Glucagon is a 29-amino acid peptide hormone produced by pancreatic alpha cells and is the principal counterregulatory hormone to insulin. FDA-approved since 1960 under the brand GlucaGen, it is the standard emergency treatment for severe hypoglycemia. It also serves as a diagnostic aid in gastrointestinal imaging. Endogenous glucagon is essential for hepatic glucose mobilization during fasting.

Last updated April 10, 2026

TL;DR

Quick summary

Glucagon is a 29-amino acid pancreatic hormone and the principal counter-regulatory hormone to insulin. FDA-approved since 1960 as GlucaGen, it is the standard emergency treatment for severe hypoglycemia and is now also available as a nasal powder (Baqsimi).

§ 01

Overview

Glucagon is a 29-amino acid peptide hormone produced by pancreatic alpha cells and is the principal counterregulatory hormone to insulin. FDA-approved since 1960 under the brand GlucaGen, it is the standard emergency treatment for severe hypoglycemia. It also serves as a diagnostic aid in gastrointestinal imaging. Endogenous glucagon is essential for hepatic glucose mobilization during fasting.

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Mechanism of action

Glucagon binds the glucagon receptor (GCGR), a class B GPCR expressed predominantly in the liver. Receptor activation stimulates adenylate cyclase, raising intracellular cAMP and activating protein kinase A (PKA), which triggers glycogenolysis (glycogen breakdown) and gluconeogenesis (de novo glucose synthesis), rapidly raising blood glucose. In pharmacological use, it reverses insulin-induced hypoglycemia within minutes. It also relaxes GI smooth muscle, making it useful as a contrast aid during endoscopy and imaging.

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Dosing protocols

PurposeRouteDosageFrequency
severe hypoglycemia (adults)intramuscular11 mgsingle dose, repeat once if no response in 15 min
severe hypoglycemia (pediatric <44 lbs)intramuscular0.50.5 mgsingle dose
GI diagnostic imagingintravenous0.252 mgsingle procedural dose

Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.

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Research summary

Glucagon has an extensively documented clinical record spanning 60+ years. GlucaGen (Novo Nordisk) and Baqsimi (nasal powder) are FDA-approved formulations. Research is exploring glucagon dual agonism alongside GLP-1 for obesity treatment. Cotadutide and other GLP-1/glucagon co-agonists are in Phase 2–3 trials for NASH and metabolic disease. Glucagon excess (hyperglucagonemia) is increasingly recognized as a driver of type 2 diabetes pathophysiology.[1][2][3][4][5]

📄This section cites 5 peer-reviewed sources. View all references →
§ 04b

Evidence grading

Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.

strong
Reverses severe hypoglycemiaFDA-approved since 1960 (GlucaGen); Murao 1993 and 60+ years of clinical use establish efficacy
strong
Nasal powder (Baqsimi) effective alternativeDemir 2021 J Diabetes Sci Tech systematic review of intranasal glucagon supports efficacy and usability
moderate
Mini-dose effective for nonsevere hypoglycemia in T1DHaymond 2017 J Clin Endocrinol Metab RCT in T1D adults established mini-dose efficacy
strong
Hepatic glycogenolysis via GCGR cAMP/PKADecades of receptor pharmacology and signal-transduction research characterize mechanism
strong
Relaxes GI smooth muscle for imagingFDA-approved diagnostic use; extensive clinical utility across endoscopy and radiology

Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data

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Side effects

Nausea
Vomiting
Headache
Injection site reactions
Hyperglycemia (rebound)
Hypokalemia (IV use)

Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.

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Common stacks

Peptides commonly paired with Glucagon for synergistic effects.

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Sourcing & access

Prescription required

Glucagon is an FDA-approved prescription medication available through licensed healthcare providers, telehealth platforms, and 503A/503B compounding pharmacies.

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Frequently asked questions

Glucagon is primarily used as emergency treatment for severe hypoglycemia when a patient cannot eat or drink. It is also used as a diagnostic aid to relax GI smooth muscle during endoscopy and imaging procedures.

Glucagon binds the glucagon receptor (GCGR) in the liver, activating glycogenolysis (glycogen breakdown) and gluconeogenesis (new glucose synthesis), rapidly raising blood glucose within minutes. It reverses insulin-induced hypoglycemia by mobilizing hepatic glucose stores.

Baqsimi is an FDA-approved nasal powder formulation of glucagon that can be administered without injection. It delivers 3 mg of glucagon nasally and is designed for bystander use in hypoglycemic emergencies, eliminating the need for reconstitution and injection.

Adults and children over 44 lbs receive 1 mg intramuscularly as a single dose. Children under 44 lbs receive 0.5 mg. The dose may be repeated once if there is no response within 15 minutes.

Yes, glucagon dual agonism alongside GLP-1 is being explored for obesity and metabolic disease. Cotadutide and other GLP-1/glucagon co-agonists are in Phase 2-3 trials for NASH, leveraging glucagon's thermogenic effects while counterbalancing its glucose-raising action with GLP-1.

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Research references

  1. Efficacy and Usability of Intranasal Glucagon for the Management of Hypoglycemia in Patients With Diabetes: A Systematic ReviewDemir S, Nawroth PP, Herzig S, Ekim Üstünel B.Journal of Diabetes Science and Technology, 2021PubMed
  2. Efficacy and Safety of Mini-Dose Glucagon for Treatment of Nonsevere Hypoglycemia in Adults With Type 1 DiabetesHaymond MW, DuBose SN, Rickels MR, et al.Journal of Clinical Endocrinology & Metabolism, 2017PubMed
  3. The Role of Glucagon in the Pathophysiology and Treatment of Type 2 DiabetesMüller TD, Finan B, Clemmensen C, DiMarchi RD, Tschöp MH.Nature Reviews Endocrinology, 2017PubMed
  4. Glucagon Receptor Signaling and Glucagon ResistanceSuppli MP, Bagger JI, Lund A, et al.International Journal of Molecular Sciences, 2019PubMed
  5. Clinical evaluation of biosynthetic glucagon treatment for recovery from hypoglycemia developed in diabetic patientsMurao S, Hirata K, Ishida T, et al.Diabetes Research and Clinical Practice, 1993PubMed
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