Side by side

1. 1.Binds glucagon receptors on liver cells, triggering glycogen breakdown and glucose release.
2. 2.Stimulates gluconeogenesis from amino acids and lactate.
3. 3.Relaxes gastrointestinal smooth muscle, which is why it is used in gut imaging.
4. 4.Stimulates insulin release from beta cells, which is used in diagnostic testing.
5. 5.Works within minutes but depends on the liver having glycogen available.

• Severe hypoglycaemia in type 1 and type 2 diabetes
• Nasal glucagon as a needle-free rescue (randomised trials)
• Beta-blocker and calcium channel blocker overdose protocols
• Gastrointestinal and biliary imaging to reduce motility
• Diagnostic testing in congenital hyperinsulinism

• Blood glucose rise within 5 to 15 minutes
• Restored consciousness in the large majority of severe hypoglycaemia episodes in trials
• Nausea and vomiting in a substantial share of treated episodes
• Relaxation of the stomach and duodenum during imaging
• Transient hyperglycaemia needing follow-up carbohydrate

• Nausea and vomiting, very common
• Headache
• Transient hyperglycaemia
• Tachycardia
• Injection-site reactions
• Rebound hypoglycaemia if no carbohydrate is eaten afterwards
• Nasal irritation with the powder

Research context only - emergency medicine. The licensed adult dose is 1 mg intramuscularly or subcutaneously, 0.5 mg if under 25 kg, or 3 mg intranasally; hospital infusion protocols for overdose run in milligrams per hour under continuous monitoring. Nasal glucagon trials measured glucose response at 30 minutes.

Research context only