Maximum Glucagon Dosage for Hypoglycemia Without IV Access in EMS Setting
The maximum dose of glucagon for severe hypoglycemia when IV access cannot be obtained is 1 mg (1000 mcg) administered intramuscularly or subcutaneously for adults and children weighing more than 25 kg (or age ≥6 years), and 0.5 mg (500 mcg) for children weighing less than 25 kg (or age <6 years). 1, 2
Standard Dosing Protocol
For adults and pediatric patients weighing >25 kg or age ≥6 years:
- Administer 1 mg (1 mL) intramuscularly or subcutaneously into the upper arm, thigh, or buttocks 2
- This is the maximum single dose regardless of patient size 1, 2
For pediatric patients weighing <25 kg or age <6 years:
- Administer 0.5 mg (0.5 mL) intramuscularly or subcutaneously 2
- Alternative weight-based dosing: 20-30 mcg/kg may be used 3
Repeat Dosing if Initial Dose Fails
If there is no response after 15 minutes, one additional dose may be administered while waiting for emergency assistance:
- Adults/children >25 kg: repeat 1 mg dose using a new kit 2
- Children <25 kg: repeat 0.5 mg dose using a new kit 2
- This represents the practical maximum total dose of 2 mg for adults or 1 mg for small children in the prehospital setting 2
Expected Response and Timing
Glucagon typically produces clinical response within 5-15 minutes after administration 1, though recovery may be slower than with IV dextrose:
- Mean time to treatment success: approximately 11 minutes with intramuscular glucagon 4
- Recovery time ranges from 8-21 minutes with IM glucagon compared to 1-3 minutes with IV glucose 5
- An unconscious patient will usually awaken within 15 minutes 2, 3
Critical Clinical Considerations
Airway protection is mandatory before glucagon administration in patients with altered mental status:
- Nausea and vomiting are common side effects, particularly with higher doses 6, 1
- The airway must be protected before administration in patients with CNS depression 6
After patient responds and can swallow safely:
- Provide oral carbohydrates immediately to restore liver glycogen and prevent secondary hypoglycemia 2, 3
- Give starchy or protein-rich foods 6
Important Limitations in the EMS Setting
Glucagon has significant limitations compared to IV dextrose when venous access is available:
- Recovery is slower with glucagon (6.5 minutes) versus IV dextrose (4.0 minutes) 7
- IV dextrose is preferred over glucagon in settings where venous access can be obtained 1
- Glucagon may be ineffective in patients with depleted glycogen stores (chronic malnutrition, alcohol use, prolonged fasting) 5
Prehospital intranasal glucagon (3 mg) is an alternative needle-free option:
- Demonstrated substantial improvement in 32% of cases, slight improvement in 30%, and no improvement in 38% of prehospital cases 8
- Mean blood glucose increase of 53.3 mg/dL in cases with substantial improvement 8
- Eliminates needle-stick injury risk to EMS personnel 8
Post-Treatment Protocol
Once glucagon is administered:
- Call for emergency assistance immediately after dose administration 2
- Monitor blood glucose after administration to ensure adequate response 1
- If patient does not respond after the second dose, continue supportive care and expedite transport for IV dextrose administration 1
- Any severe hypoglycemic episode requiring external assistance mandates reevaluation of the diabetes management plan 9