glucagon (gloo-ka-gon) GlucaGen

 Indications

Acute management of severe hypoglycemia when administration

of glucose is not feasible. Facilitation of radiographic

examination of the GI tract. Unlabeled

Use: Antidote to: Beta blockers, Calcium channel

blockers.

Action

Stimulates hepatic production of glucose from glycogen

stores (glycogenolysis). Relaxes the musculature of the

GI tract (stomach, duodenum, small bowel, and colon),

temporarily inhibiting movement. Has positive

inotropic and chronotropic effects. Therapeutic Effects:

Increase in blood glucose. Relaxation of GI

musculature, facilitating radiographic examination.

Pharmacokinetics

Absorption: Well absorbed following IM and subcut

administration.

Distribution: Unknown.

Metabolism and Excretion: Extensively metabolized

by the liver, plasma, and kidneys.

Half-life: 8–18 min.

TIME/ACTION PROFILE

ROUTE ONSET PEAK DURATION

IM (hyperglycemic

action)

within 10 min 30 min 12–27 min

IV (hyperglycemic

action)

1 min 5 min 9–17 min

Subcut (hyperglycemic

action)

within 10 min 30–45 min 60–90 min

IV (effect on

GI musculature)

45 sec (for

0.25–2-mg

dose)

unknown 9–17 min

(0.25–0.5-

mg dose);

22–25 min

(2-mg

dose)

IM (effect on

GI musculature)

8–10 min (1-

mg dose);

4–7 min (2-

mg dose)

unknown 9–27 min (1-

mg dose);

21–32 min

(2-mg

dose)

Contraindications/Precautions

Contraindicated in: Hypersensitivity; Pheochromocytoma;

Some products contain glycerin and phenol—

avoid use in patients with hypersensitivities to

these ingredients.

Use Cautiously in: History suggestive of insulinoma

or pheochromocytoma; Prolonged fasting, starvation,

adrenal insufficiency, or chronic hypoglycemia (low

levels of releasable glucose); When used to inhibit GI

motility, use cautiously in geriatric patient with cardiac

disease or diabetics; OB: Should be used during pregnancy

only if clearly needed; Lactation: Safety not established.

Adverse Reactions/Side Effects

CV: hypotension. GI: nausea, vomiting. Misc: hypersensitivity

reactions including ANAPHYLAXIS.

Interactions

Drug-Drug: Large doses may enhance the effect of

warfarin. Negates the response to insulin or oral hypoglycemic

agents. Phenytoin inhibits the stimulant

effect of glucagon on insulin release. Hyperglycemic effect is intensified and prolonged by epinephrine. Patients

on concurrent beta blocker therapy may have a

greater increase in heart rate and BP.

Route/Dosage

Hypoglycemia

IV, IM, Subcut (Adults and Children 25 kg): 1

mg; may be repeated in 15 min if necessary.

IV, IM, Subcut (Children 25 kg ): 0.5 mg or

0.02–0.03 mg/kg; may be repeated in 15 min if necessary.

IV, IM, Subcut (Children 6 yr and unknown

weight): 1 mg; may be repeated in 15 min if necessary.

IV, IM, Subcut (Children 6 yr and unknown

weight): 0.5 mg or 0.02–0.03 mg/kg; may be repeated

in 15 min if necessary.

Radiographic Examination of the GI Tract

IM, IV (Adults): 0.25–2 mg; depending on location

and duration of examination (0.5 mg IV or 2 mg IM for

relaxation of stomach; for examination of the colon 2

mg IM 10 min before procedure).

Antidote (unlabeled)

IV (Adults): To beta blockers—50–150 mcg (0.05–

0.15 mg)/kg, followed by 1–5 mg/hr infusion. To calcium

channel blockers—2 mg; additional doses determined

by response.

Availability

Powder for injection: 1-mg (equivalent to 1 unit) vials

as an emergency kit for low blood glucose and as a

diagnostic kit.