What is the preferred route of administration for glucagon (Glucagon), intravenous (IV) or intramuscular (IM), in the management of a food bolus obstruction?

Glucagon for Food Bolus Obstruction: IV vs IM Administration

Direct Answer

Glucagon is NOT recommended as a primary treatment for food bolus obstruction, regardless of route of administration (IV or IM), and urgent endoscopic intervention should be pursued instead. 1

Evidence-Based Rationale

Primary Management: Endoscopy, Not Pharmacotherapy

The British Society of Gastroenterology (BSG) 2022 guidelines explicitly state that there is no evidence that conservative treatments such as glucagon are helpful in the management of food bolus obstruction. 1 The key to initial management is:

• Reassurance and assessment of perforation risk 1
• Urgent interventional endoscopy to remove the food bolus and obtain biopsies (eosinophilic esophagitis is the most common cause in 30-46% of cases) 1
• Endoscopy should occur on the next available list or as an immediate emergency depending on clinical presentation 1

Historical Context of Glucagon Use

While older literature from the 1970s-1980s described glucagon use for food bolus obstruction, this practice has been abandoned based on lack of efficacy:

• Glucagon works by relaxing the lower esophageal sphincter, but food bolus obstructions typically occur in the mid-to-upper esophagus where this mechanism is irrelevant 2, 3, 4
• Retrospective data showed glucagon was less effective when meat was the impacted food (70% vs 90% failure rate) and when esophageal rings/strictures were present 2
• Success rates were poor overall, and the temporal relationship between administration and relief was often coincidental with spontaneous passage 2, 5

When Glucagon IS Indicated: Anaphylaxis Context

The confusion may arise because glucagon IS recommended in emergency settings, but specifically for anaphylaxis in patients on beta-blockers, not for food bolus obstruction:

• Dosing for anaphylaxis: 1-5 mg IV over 5 minutes in adults (20-30 mcg/kg, maximum 1 mg in children), followed by infusion of 5-15 mcg/min 1
• This indication is for epinephrine-unresponsive anaphylaxis, as glucagon has inotropic/chronotropic effects not mediated through beta-receptors 1
• Aspiration precautions are mandatory as glucagon causes nausea and vomiting 1

Route Comparison (When Glucagon IS Used)

For the specific question of IV vs IM when glucagon is appropriately indicated:

• IV administration (1-5 mg over 5 minutes) is used for anaphylaxis in beta-blocker patients 1
• IM/SC administration (1 mg) is preferred for hypoglycemia 6
• The older food bolus literature used IV glucagon (1 mg), but this practice is now obsolete 3, 4

Clinical Pitfalls to Avoid

• Do not delay endoscopy while attempting pharmacologic management with glucagon or other agents (nitrates, benzodiazepines, effervescent agents) 1
• Do not confuse glucagon indications: It is for anaphylaxis (beta-blocker patients) and hypoglycemia, NOT food bolus obstruction 1, 6
• Obtain biopsies at index endoscopy (minimum 6 biopsies from 2 levels) to diagnose underlying eosinophilic esophagitis 1
• If considering any smooth muscle relaxant, oral nitroglycerin solution (0.4 mg in 10 mL water) has more recent case report evidence than glucagon, though still not guideline-recommended 7

Bottom Line Algorithm

1. Patient presents with food bolus obstruction → Assess airway and perforation risk 1
2. Do NOT administer glucagon (or other pharmacologic agents) 1
3. Arrange urgent endoscopy (same day or emergent) 1
4. Obtain 6+ esophageal biopsies at index endoscopy to diagnose eosinophilic esophagitis 1
5. If spontaneous resolution occurs, still arrange elective endoscopy with biopsies before discharge 1