What is the recommended intramuscular (IM) glucagon dosage for a patient experiencing hypoglycemia?

Intramuscular Glucagon Dosing for Hypoglycemia

For severe hypoglycemia, administer 1 mg (1000 mcg) of glucagon intramuscularly for adults and children weighing ≥25 kg (or age ≥6 years), and 0.5 mg (500 mcg) for children weighing <25 kg (or age <6 years). 1, 2, 3

Standard Dosing Protocol

Adults and Larger Children

• Administer 1 mg (1000 mcg) IM as a single dose into the upper arm, thigh, or buttocks 1, 3
• This applies to all patients weighing more than 25 kg or age 6 years and older 2, 3
• No dose adjustment is needed for renal impairment 2

Pediatric Patients (Smaller Children)

• Administer 0.5 mg (500 mcg) IM as a single dose for children weighing less than 25 kg or age less than 6 years 1, 3
• Use the same injection sites: upper arm, thigh, or buttocks 3

Repeat Dosing Considerations

• If no response occurs within 15 minutes, you may administer one additional dose at the same strength (1 mg or 0.5 mg depending on weight/age) while waiting for emergency assistance 3
• However, if the patient still does not respond adequately after the initial dose, switch to IV dextrose (20-40 mL of 50% glucose solution) rather than continuing to repeat glucagon 1, 2
• The slower response time with glucagon (5-15 minutes) makes IV dextrose preferable when venous access is available 1, 2, 4

Critical Post-Administration Steps

Immediate Actions

• Call for emergency assistance immediately after administering glucagon 3
• Monitor blood glucose every 15 minutes until levels exceed 70 mg/dL 2
• Expect blood glucose to increase within 5-15 minutes after administration 1, 4

Once Patient Responds

• When the patient regains consciousness and can swallow safely, immediately give 15-20 g of oral carbohydrates to restore liver glycogen and prevent secondary hypoglycemia 2, 3
• Follow with a meal or protein-containing snack 2
• Continue monitoring to avoid overcorrection causing hyperglycemia 2

Common Pitfalls and Safety Considerations

Side Effects to Anticipate

• Nausea and vomiting are common, particularly with higher doses 1, 2, 4
• Protect the airway before administering glucagon in patients with altered mental status, seizures, or central nervous system depression 1, 2
• Watery eyes and runny nose may occur with intranasal formulations but are not relevant for IM administration 5

Critical Safety Points

• Never attempt oral glucose in a seizing or unconscious patient due to aspiration risk 2
• Do not delay glucagon administration to obtain IV access in the prehospital or home setting 2
• Glucagon may be less effective in patients with depleted glycogen stores (prolonged fasting, chronic hypoglycemia, alcohol intoxication) 2

Practical Administration Tips

• Newer ready-to-inject glucagon formulations are preferred over traditional reconstitution kits because they are easier for untrained caregivers to administer and result in more rapid correction 1
• If using traditional kits requiring reconstitution, inject all diluent into the powder vial, shake gently until completely dissolved, and use immediately 3
• The reconstituted solution should be clear and colorless; discard if cloudy or contains particles 3

Who Should Have Glucagon Prescribed

• All individuals treated with insulin—even basal-only regimens—should be prescribed glucagon 1
• Consider glucagon for persons taking sulfonylureas who meet criteria for high hypoglycemia risk 1
• Train family members, roommates, school personnel, childcare professionals, and coworkers on glucagon administration 1, 4