glucagon

glucagon

 [gloo´kah-gon]

a polypeptide hormone secreted by the alpha cells of the islets of langerhans in response to hypoglycemia or to stimulation by growth hormone. It increases blood glucose concentration by stimulating glycogenolysis in the liver and can be administered parenterally to relieve severe hypoglycemia from any cause, especially hyperinsulinism. Because it slows motility of the gastrointestinal tract, it is also used as an aid in gastrointestinal radiography.

glucagon stimulation test a provocative test of growth hormone (GH) function in which the fasting serum level of GH is measured after administration of glucagon.

glucagon

GlucaGen

Pharmacologic class: Antihypoglycemic

Therapeutic class: Insulin antagonist

Pregnancy risk category B

Action

Increases blood glucose concentration by converting glycogen in liver to glucose. Also relaxes GI smooth muscle.

Availability

Powder for injection: 1-mg vials

Indications and dosages

➣ Severe hypoglycemia

Adults and children weighing more than 20 kg (44 lb): 1 mg subcutaneously, I.M., or I.V.

Children weighing 20 kg (44 lb) or less: 20 to 30 mcg/kg or 0.5-mg dose subcutaneously, I.M., or I.V.

➣ Diagnostic aid for radiologic examination

Adults: 0.25 to 2 mg I.V. or 1 to 2 mg I.M. before radiologic procedure

Contraindications

• Hypersensitivity to drug

• Pheochromocytoma

Precautions

Use cautiously in:

• cardiac disease, adrenal insufficiency, chronic hypoglycemia

• history suggesting insulinoma or pheochromocytoma

• elderly patients

• pregnant or breastfeeding patients.

Administration

☞ Use only in hypoglycemic emergencies for patients with diabetes mellitus.

• Mix drug in 1-mg vial with 1 ml of diluent supplied by manufacturer.

• For I.V. injection, give 1 mg over 1 minute.

• Use drug immediately after preparing; discard unused portion.

☞ Patient should respond within 15 minutes. Because of potential serious adverse reactions linked to prolonged cerebral hypoglycemia, give I.V. glucose if patient fails to respond to glucagon.

• Give patient carbohydrate-rich foods as soon as he's alert.

• Dilute diagnostic aid doses above 2 mg with sterile water for injection.

Adverse reactions

CV: hypotension

GI: nausea, vomiting

Metabolic: hypokalemia (with overdose)

Respiratory: bronchospasm, respiratory distress

Skin: urticaria, rash

Interactions

Drug-drug. Anticoagulants: enhanced anticoagulant effect

Drug-diagnostic tests. Potassium: decreased level

Patient monitoring

• Monitor blood glucose level.

• Monitor patient for aspiration.

• Assess blood pressure, electrolyte levels, and respiratory status.

Patient teaching

• Teach patient and family members the proper technique and timing for using this emergency drug.

☞ Emphasize importance of contacting prescriber right away if hypoglycemic emergency occurs.

☞ Tell caregiver or family member to arouse patient immediately and give additional carbohydrate by mouth as soon as patient can tolerate it.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.

glu·ca·gon

(glū'kă-gon), [MIM*138030]

A hormone consisting of a straight-chain polypeptide of 29 amino acyl residues, extracted from pancreatic alpha cells. Parenteral administration of 0.5-1 mg results in prompt mobilization of hepatic glycogen, thus elevating blood glucose concentration. It activates hepatic phosphorylase, thereby increasing glycogenolysis, decreases gastric motility and gastric and pancreatic secretions, and increases urinary excretion of nitrogen and potassium; it has no effect on muscle phosphorylase. As the hydrochloride, it is used in the treatment of type I glycogenosis (von Gierke disease) and hypoglycemia, particularly hypoglycemic coma due to exogenously administered insulin.

Synonym(s): HG factor, hyperglycemic-glycogenolytic factor, pancreatic hyperglycemic hormone

[glucose + G. agō, to lead]

glucagon

(glo͞o′kə-gŏn′)

n.

A hormone produced by the pancreas that stimulates an increase in blood sugar levels, thus opposing the action of insulin.

glucagon

Endocrinology A 29-residue polypeptide hormone, produced by pancreatic islet α cells that opposes insulin, activates hepatic phosphorylase, ↓ gastric motility, secretion and muscle mass, promotes glycogenolysis, ↑ serum glucose, ↑ ketogenesis and liver incorporation of amino acids and urinary excretion of Na+ and K+ ↑ in Neonates, glucagonoma, DM ↓ in Some Pts with DM, hypoglyecemia

glu·ca·gon

(glū'kă-gon)

A hormone produced by pancreatic alpha cells. Parenteral administration of 0.5-1 mg results in prompt mobilization of hepatic glycogen, thus elevating blood glucose concentration. It is used in the treatment of glycogen storage disease (von Gierke) and hypoglycemia, particularly hypoglycemic coma due to exogenously administered insulin.

[glucose + G. agō, to lead]

glucagon

One of the four hormones produced by the Islet cells of the PANCREAS, the others being insulin, somatostatin and a polypeptide of unknown function. The action of glucagon opposes that of insulin. It causes liver glycogen, a polysaccharide, to break down to glucose, thereby increasing the amount of sugar in the bloodstream. It can also mobilize fatty acids for energy purposes. Glucagon is a 20-amino acid peptide secreted by the alpha Islet cells. A brand name is Glucagen.

glucagon

a polypeptide of 29 amino acids produced by the alpha cells in the ISLETS OF LANGERHANS of the pancreas of vertebrates. Glucagon acts as a hormone, having the opposite effect to INSULIN, in causing the breakdown of liver GLYCOGEN and the release of glucose into the blood.

Glucagon

A hormone produced in the pancreas that raises the level of glucose in the blood. An injectable form of glucagon, which can be bought in a drug store, is sometimes used to treat insulin shock.

Mentioned in: Hypoglycemia, Hypotonic Duodenography

glu·ca·gon

(glū'kă-gon) [MIM*138030]

A hormone consisting of a straight-chain polypeptide; activates hepatic phosphorylase, thereby increasing glycogenolysis, decreases gastric motility and gastric and pancreatic secretions.

[glucose + G. agō, to lead]