glucagon

Action and Spectrum

Actions and Spectrum:

glucagon raises blood glucose levels. It helps in converting the stored the glycogen into glucose.

The spectrum of glucagon’s actions includes:

• Stimulation of liver glycogenolysis (breakdown of glycogen to glucose)
• Stimulation of gluconeogenesis (production of glucose from non-carbohydrate sources)
• Inhibition of insulin secretion
• Inhibition of glucose uptake and utilization in peripheral tissues
• Promotion of fatty acid mobilization and oxidation in adipose tissue

Drug Interaction

Adverse Reaction

>10%:

Nausea (36-54%)

Vomiting (14-23%)

Hypoglycemia (27-54%)

Hyperglycemia (8-14%)

Headache (15%)

1-10%:

Injection site reaction (9%)

Abdominal pain (8%)

Urticaria (8%)

Injection site discomfort (8%)

<1%:

Hypoglycemia coma

Hypoglycemia

Vomiting

Black Box Warning

Contraindication / Caution

Contraindication/Caution:

Contraindications of glucagon include:

•  Allergic reactions: People allergic to glucagon or its components should not use it.
• Liver disease: People with liver disease should use glucagon cautiously, as it can affect liver function.

People should take caution if they have:

•  Low blood sugar levels (hypoglycemia): glucagon should only be used if recommended by a healthcare provider.
• Severe kidney disease: People with severe kidney disease should use glucagon cautiously, as it can affect kidney function.
• Chronic conditions: People with chronic conditions such as diabetes, heart disease, or high blood pressure should use glucagon cautiously, as it can affect blood glucose and blood pressure levels.

Pregnancy / Lactation

Pregnancy consideration:

Category C.

Breastfeeding warnings:

Use with caution during breastfeeding.

Pregnancy category:

Category A: well-controlled and Satisfactory studies do not show risk to the fetus in the first/later trimester.

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women.

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.

Category D: adequate data available with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.

Category N: No data is available for the drug under this category.

Pharmacology

Pharmacology

glucagon promotes the breakdown of fatty acids into ketones, which can be used as an alternative energy source. These actions help to raise blood glucose levels and counteract the effects of insulin, which decreases blood glucose levels. glucagon is used clinically for treating severe hypoglycemia (low blood sugar) in patients with diabetes and for diagnostic purposes in radiology.

Pharmacodynamics:

• Binding to Receptors: glucagon binds to specific receptors (glucagon receptors) on target cells. Like liver and muscle cells, they trigger intracellular signaling pathways.
• Increased cAMP levels: The glucagon binding to its receptors activates adenylyl cyclase. It leads to increased cyclic adenosine monophosphate (cAMP) levels.
• Activation of Protein Kinase A: The elevated levels of cAMP activate protein kinase A (PKA), which then phosphorylates (adds a phosphate group to) target proteins.
• Glycogenolysis and Gluconeogenesis: PKA activates the liver’s enzymes in glycogenolysis and gluconeogenesis, increasing glucose production and releasing it into the bloodstream.
• Lipolysis: PKA also activates lipase, an enzyme involved in breaking stored fats into fatty acids and glycerol, which can be used as an alternative energy source.
• These glucagon actions help increase blood glucose levels and counteract insulin’s effects, decreasing blood glucose levels.

Pharmacokinetics:

•  Absorption: glucagon is administered subcutaneously (under the skin) or intramuscularly (into a muscle). After injection, glucagon is rapidly absorbed into the bloodstream.
• Distribution: Once in the bloodstream, glucagon is distributed to target cells such as liver and muscle cells.
• Metabolism: glucagon has a short half-life in the bloodstream and is rapidly degraded by the liver.
• Excretion: The degraded products of glucagon are excreted by the kidneys into the urine.

Adminstartion

Administration:

glucagon is administered intravenously, intramuscularly, or subcutaneously by diluting it with sterile water for injection. The IM dose is given to the arm/thigh/buttocks.

Patient Information Leaflet

Patient information leaflet

Generic Name: glucagon

Pronounced: gloo-kuh-gawn

Why do we use glucagon?

• Treatment of Hypoglycemia: glucagon is used to treat severe hypoglycemia when the patients cannot eat or drink. A glucagon injection raises blood sugar levels quickly by stimulating the liver to convert stored glycogen into glucose and release it into the bloodstream.
• Diagnostic Purposes in Radiology: glucagon can be used as a diagnostic tool in radiology. During a glucagon stimulation test, glucagon is administered to a patient, and the resulting increase in blood glucose levels can be used to assess the function of the pancreas and its ability to produce insulin.
• Research Purposes: glucagon is also used to study the regulation of glucose and lipid metabolism.