glucagon
Glucagon Diagnostic Kit, Glucagon Emergency Kit, GlucaGen Emergency Kit

Pharmacologic classification: antihypoglycemic
Therapeutic classification: glucose-elevating drug, diagnostic agent
Pregnancy risk category B


Available forms
Available by prescription only
Powder for injection: 1 mg (1 unit)/vial, 10 mg (10 units)/vial

Indications and dosages
 Severe hypoglycemia. Adults and children who weigh more than 20 kg (44 lb): 1 mg S.C., I.M., or I.V. May repeat dose after 15 minutes if patient fails to respond. When patient responds, give supplemental carbohydrates.
Children who weigh less than 20 kg: 0.5 mg S.C., I.M., or I.V. Or, 20 to 30 mcg/kg. May repeat dose after 15 minutes if patient fails to respond. When patient responds, give supplemental carbohydrates.
 Diagnostic aid for radiographic examination of stomach, duodenum, and small intestine. Adults: 1 or 2 mg I.M. or 0.25 to 2 mg I.V. For relaxation of the stomach, use 0.5. mg I.V. or 2 mg I.M.

Pharmacodynamics
Antihypoglycemic action: Glucagon increases plasma glucose levels and causes smooth muscle relaxation and an inotropic myocardial effect because of the stimulation of adenylate cyclase to produce cAMP. The cAMP initiates a series of reactions that leads to the degradation of glycogen to glucose. Hepatic stores of glycogen are needed for glucagon to exert an antihypoglycemic effect.
Diagnostic action: The mechanism by which glucagon relaxes smooth muscles of the GI tract hasn’t been fully defined.

Pharmacokinetics
Absorption: Glucagon is destroyed in the GI tract; therefore, it must be given parenterally. Administration to comatose hypoglycemic patients (with normal liver glycogen stores) usually produces a return to consciousness within 20 minutes.
Distribution: Not fully understood.
Metabolism: Degraded extensively by the liver, in the kidneys and plasma, and at its tissue receptor sites in plasma membranes.
Excretion: Metabolic products are excreted by the kidneys. Half-life is about 3 to 10 minutes.

Route Onset Peak Duration
I.V. Immediate 30 min 60-90 min
I.M., S.C. Unknown Unknown Unknown


Contraindications and precautions
Contraindicated in patients hypersensitive to drug and in those with pheochromocytoma. Use cautiously in patients with insulinoma.

Interactions
Drug-drug. Anticoagulants: Enhances anticoagulant effect. Monitor patient for bleeding.
Epinephrine: Increases and prolongs hyperglycemic effect. Monitor blood glucose levels.
Phenytoin: Appears to inhibit glucagon-induced insulin release. Use cautiously as a diagnostic agent in patients with diabetes mellitus.

Adverse reactions
CV: hypotension.
GI: nausea, vomiting.
Metabolic: hypokalemia.
Respiratory: respiratory distress.
Other: hypersensitivity reactions (bronchospasm, rash, dizziness, light-headedness).

Effects on lab test results
• May decrease potassium levels.

Overdose and treatment
Overdose may cause nausea, vomiting, diarrhea, gastric hypotonicity, and hypokalemia.
 Treat symptomatically.

Special considerations
• For I.V. drip infusion, glucagon is compatible with dextrose solution but forms a precipitate in chloride solutions.
• Solutions mixed with diluent are stable for 48 hours when stored at 41° F (5° C). Following reconstitution with sterile water, use immediately. Discard unused portion.
• Glucagon has a positive inotropic and chronotropic action on the heart and may be used to treat beta blocker overdose.
Breast-feeding patients
• It isn’t known whether drug appears in breast milk.
Pediatric patients
• Glucagon has been used safely and effectively for the treatment of hypoglycemia in children. Safety and efficacy in diagnostic procedures haven’t been established.

Patient education
• Teach patient and family members the signs and symptoms of hypoglycemia. Explain when to call for emergency medical help.
• Provide patient and family members with instructions on how to mix and inject drug properly.
• Tell patient and family members to expect response usually within 20 minutes after injection.

Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE THREATENING.
◆ Canada only
◇ Unlabeled clinical use