Glucagon

Glucagon is primarily employed in acute medical settings to address critically low blood glucose levels.

• Emergency treatment of severe hypoglycemia in individuals with diabetes.
• Management of hypoglycemia when oral glucose is not feasible.
• Diagnostic aid in evaluating pancreatic function during certain endocrine tests.
• Support for patients experiencing insulin overdose or prolonged fasting.
• Adjunct therapy in cases of beta‑blocker or calcium channel blocker overdose (off‑label use in some regions).

Side effects of glucagon vary in frequency and severity, ranging from mild reactions to rare serious events, and are typically observed shortly after the drug is administered.

Common

• Nausea or vomiting, often occurring shortly after injection.
• Flushing or a sensation of warmth across the face and neck.
• Headache or dizziness, typically mild and transient.
• Transient increase in heart rate (tachycardia) that resolves without intervention.
• Mild abdominal discomfort or cramping.
• Temporary rise in blood pressure that normalizes quickly.
• Mild sweating or feeling of anxiety after administration.

Serious

• Severe allergic reaction (anaphylaxis) presenting with rash, swelling, hives, or breathing difficulty.
• Cardiac arrhythmias or chest pain, particularly in patients with pre‑existing heart conditions.

When using glucagon, several precautions should be considered to ensure safe administration and to minimize potential risks.

• Verify patient identity and confirm indication before injection.
• Assess for known hypersensitivity to glucagon or any component of the formulation.
• Use caution in patients with cardiovascular disease, as glucagon may affect heart rate and blood pressure.
• Avoid administration in individuals with pheochromocytoma due to risk of hypertensive crisis.
• Ensure proper storage conditions; glucagon should be kept refrigerated and protected from light.
• Do not reuse single‑use vials or syringes to prevent contamination.
• Monitor blood glucose levels after administration to evaluate therapeutic response.

Glucagon may interact with other medications, influencing its effectiveness or increasing the risk of adverse effects.

Avoid

• Beta‑blockers, which can blunt the glucose‑raising effect of glucagon.
• Calcium channel blockers, as combined use may exacerbate cardiovascular side effects.

Use with caution

• Insulin or other hypoglycemic agents; concurrent use may require close monitoring of blood glucose.
• Oral anticoagulants, as glucagon can affect platelet function in rare cases.
• Monoamine oxidase inhibitors (MAOIs), which may potentiate cardiovascular responses.
• Diuretics, especially thiazides, because electrolyte shifts may alter glucagon’s action.