Glucagon Dosing for Beta-Blocker Overdose
For adults with beta-blocker overdose causing refractory hypotension or bradycardia, administer an initial IV bolus of 3-10 mg over 3-5 minutes, followed by a continuous infusion of 3-5 mg/hour (0.05-0.15 mg/kg/hour), titrated to hemodynamic response. For children, use 0.03-0.15 mg/kg bolus (maximum 1 mg initially) followed by 0.07 mg/kg/hour infusion (maximum 5 mg/hour) 1.
Adult Dosing Algorithm
Initial Bolus Dose
- Standard dose: 3-10 mg IV administered slowly over 3-5 minutes 1
- Alternative dosing from older guidelines: 1-5 mg IV over 5 minutes 2
- The 2010 AHA guidelines represent the most authoritative recommendation with the higher dose range
Continuous Infusion
- Start at 3-5 mg/hour and titrate upward based on hemodynamic response 1
- Maximum infusion rate: Not explicitly defined, but may require >100 mg over 24 hours in severe cases 1
- Titrate to achieve adequate mean arterial pressure and evidence of good perfusion
Repeat Dosing
- If inadequate response after initial bolus, the infusion should be started immediately rather than repeating boluses
- The FDA label for hypoglycemia allows repeat 1 mg doses every 15 minutes 3, but this is NOT the protocol for beta-blocker toxicity
Pediatric Dosing Algorithm
Initial Bolus Dose
- 0.03-0.15 mg/kg IV over several minutes 4
- Maximum initial dose: 1 mg for hypoglycemia 4
- Alternative dosing: 20-30 mcg/kg (maximum 1 mg) 2
Continuous Infusion
Repeat Dosing for Hypoglycemia Context
- For children <20 kg with hypoglycemia: 0.5 mg (0.5 mL) may be repeated after 15 minutes 3
- For children ≥20 kg: 1 mg may be repeated after 15 minutes 3
Critical Implementation Details
Preparation and Administration
- Reconstitute with sterile water rather than manufacturer-supplied diluent for doses ≥2 mg to reduce volume 4
- Administer IV push slowly over 3-5 minutes to minimize side effects
- Ensure adequate supply is available—severe cases may require >100 mg in 24 hours 1
Monitoring Requirements
- Continuous hemodynamic monitoring is essential 1
- Monitor for adequate mean arterial pressure and perfusion
- Titrate infusion rate to clinical response, not to fixed endpoints
Airway Protection
Protect the airway BEFORE glucagon administration in patients with CNS depression, as glucagon commonly causes vomiting 1. This is a critical safety consideration that cannot be overlooked.
Antiemetic Prophylaxis
- Consider ondansetron or other antiemetics prophylactically
- Despite prophylaxis, nausea occurs in approximately 80% of patients receiving high-dose glucagon 5
- Vomiting occurred in 9.7% of cases in one series despite antiemetic use 6
Evidence Quality and Limitations
The 2010 AHA guidelines 1 and 2023 AHA focused update 7 provide Class IIb, Level of Evidence C recommendations for glucagon in beta-blocker toxicity. This means glucagon "may be reasonable" but evidence is limited to case reports and animal studies. The 2025 AHA guidelines 8 maintain similar recommendations.
Recent human data shows modest effects: a case series found mean heart rate increase of only 4 bpm and median systolic BP increase of 4.5 mmHg 6. However, a randomized trial in healthy volunteers demonstrated more robust hemodynamic effects with 50 mcg/kg bolus, increasing heart rate by 13 bpm and systolic BP by 15.6 mmHg 5.
The evidence supporting glucagon is weaker than for high-dose insulin therapy, which has a Class 1, Level B-NR recommendation in the 2023 AHA guidelines 7. Consider glucagon as second-line or adjunctive therapy when vasopressors and high-dose insulin are insufficient.
Common Pitfalls
- Underdosing: Using hypoglycemia doses (1 mg) rather than toxicology doses (3-10 mg bolus)
- Inadequate supply: Not ensuring sufficient glucagon is available for prolonged infusions
- Aspiration risk: Failing to protect airway before administration in obtunded patients
- Expecting dramatic response: Glucagon effects may be modest and transient 6
- Drug interactions: Concomitant dopamine, isoproterenol, or milrinone may decrease glucagon effectiveness 1