What is the recommended injection site for glucagon in an adult diabetic patient experiencing severe hypoglycemia?

Glucagon Injection Sites

Glucagon should be injected subcutaneously or intramuscularly into the upper arm, thigh, or buttocks for the treatment of severe hypoglycemia in adults. 1

Approved Injection Sites

The FDA-approved sites for glucagon administration are:

• Upper arm 1
• Thigh 1
• Buttocks 1

These sites can be used for both subcutaneous and intramuscular injection. 1 Healthcare providers may also administer glucagon intravenously, though this should only occur under medical supervision. 1

Route of Administration

Glucagon is administered subcutaneously or intramuscularly, not intravenously in emergency settings. 1 The subcutaneous or intramuscular routes are preferred for emergency use by caregivers because they do not require venous access and can be administered quickly during a hypoglycemic crisis. 1, 2

Practical Considerations for Site Selection

While all three sites (upper arm, thigh, buttocks) are FDA-approved, truncal sites like the buttocks may be preferable to limb sites based on injection technique principles. 3 The buttocks have thicker subcutaneous tissue (median distance to muscle of 16.9 mm) compared to the thigh (10.9 mm), which provides a larger margin of safety. 4

However, in an emergency hypoglycemic situation, the most accessible site should be used without delay. 1 The priority is rapid administration—ready-to-use glucagon autoinjectors can be prepared and administered in approximately 27 seconds, compared to 97 seconds for traditional glucagon emergency kits requiring reconstitution. 2

Dosing by Weight

• Adults and children weighing >25 kg or ≥6 years: 1 mg (1 mL) injected into upper arm, thigh, or buttocks 1
• Children weighing <25 kg or <6 years: 0.5 mg (0.5 mL) injected into upper arm, thigh, or buttocks 1

Expected Response Time

After proper administration, patients typically achieve plasma glucose >70 mg/dL or an increase ≥20 mg/dL within approximately 10-14 minutes. 2 If there is no response after 15 minutes, an additional dose may be administered while waiting for emergency assistance. 1

Critical Safety Point

Avoid injecting into areas with lipohypertrophy, scars, or damaged tissue, as absorption will be unpredictable. 5, 6 While this is more commonly discussed for insulin injections, the same principle applies to any subcutaneous medication including glucagon. 3