Glucagon Pediatric Dose — Toxicology & Hypoglycemia
Glucagon is an endogenous pancreatic hormone that raises blood glucose by stimulating hepatic glycogenolysis and gluconeogenesis, and exerts positive inotropic and chronotropic effects via cAMP-mediated pathways independent of adrenergic receptors. In pediatric toxicology and emergency practice, it is used primarily for hypoglycemia secondary to insulin excess and as an antidote in beta-blocker overdose. Its non-adrenergic mechanism makes it particularly valuable when catecholamine-mediated therapies are insufficient or contraindicated.
Pediatric Dosing
Hypoglycemia Secondary to Insulin Excess
- 0.02 mg/kg IV, IM, or SQ
- Maximum single dose: 1 mg
- May repeat every 20 minutes as needed
Worked example: For a 20 kg child: 20 × 0.02 mg/kg = 0.4 mg. For a 70 kg adolescent, the dose would be capped at 1 mg.
Beta-Blocker Overdose
- Children: 0.025–0.05 mg/kg IV bolus, followed by a continuous infusion of 0.07 mg/kg/hr
- Adolescents: 2–3 mg IV bolus, followed by a continuous infusion of 5 mg/hr
Worked example (child): For a 15 kg child: bolus dose = 15 × 0.025 to 15 × 0.05 mg/kg = 0.375–0.75 mg IV; infusion = 15 × 0.07 mg/kg/hr = 1.05 mg/hr. Consult institutional protocol for preparation and concentration guidance.
Indications and Clinical Context
Glucagon is indicated for hypoglycemia secondary to insulin excess when IV dextrose is unavailable or insufficient, providing a rapid alternative via IM or SQ routes in patients without reliable venous access. Its efficacy depends on adequate hepatic glycogen stores, which may be limited in malnourished or prolonged-fasting patients.
In beta-blocker toxicity, glucagon is a recommended antidote per toxicology guidelines due to its ability to bypass the blocked beta-adrenergic receptor and directly stimulate cardiac adenylate cyclase, improving heart rate and contractility. It is considered a first-line adjunct in hemodynamically significant beta-blocker overdose, alongside supportive care and high-dose insulin euglycemic therapy as per institutional and Poison Control Center guidance.
Administration and Monitoring
For hypoglycemia, glucagon may be administered IV, IM, or SQ; IV is preferred in the acute inpatient setting for fastest onset. For beta-blocker overdose, IV bolus followed by continuous infusion is the standard approach. Reconstitute lyophilized glucagon with the provided diluent immediately before use; do not use if the solution appears cloudy or contains particulate matter.
- Adverse effects: Nausea and vomiting are common and may increase aspiration risk in obtunded patients; position patient accordingly.
- Hyperglycemia: Monitor blood glucose closely following administration, particularly with repeated dosing or infusions.
- Hypokalemia: Has been reported with high-dose infusions used in beta-blocker overdose; monitor serum electrolytes.
- Contraindications: Pheochromocytoma (may cause catecholamine release and severe hypertension); insulinoma (may provoke rebound hypoglycemia).
- Consult Poison Control Center and institutional protocol for duration and titration of infusions in overdose management.
Disclaimer: This article is an educational reference summarizing standard pediatric dosing values. It is not a substitute for clinical judgment. Always verify doses against institutional protocols, the current edition of authoritative references (e.g., Lexicomp, Harriet Lane Handbook, PALS guidelines), the patient’s accurate weight, and any patient-specific factors (renal/hepatic function, allergies, comedications) before administration.