Glucagon Dosing for ERCP
For duodenal relaxation during ERCP, administer 0.25-0.5 mg glucagon intravenously or 1 mg intramuscularly 1.
Dosing Algorithm
The FDA-approved dosing for gastrointestinal motility inhibition during ERCP depends on the target anatomy and route of administration:
Intravenous Administration (Preferred)
- Duodenum and small bowel relaxation: 0.25-0.5 mg IV 1
- Stomach relaxation: 0.5 mg IV 1
- Onset is rapid when given intravenously, allowing for immediate procedural benefit
Intramuscular Administration (Alternative)
- Duodenum and small bowel: 1 mg IM 1
- Stomach: 2 mg IM 1
- Colon: 2 mg IM approximately 10 minutes prior to procedure 1
Evidence Supporting This Dosing
The FDA drug label provides the most authoritative guidance, specifying that doses for relaxation of the duodenum and small bowel range from 0.25-0.5 mg IV or 1 mg IM 1. This is the standard of care for procedural use.
Research evidence supports the 1 mg dose as effective. A randomized study comparing glucagon to hyoscine N-butyl bromide used 1 mg glucagon intravenously and found it equally effective for ERCP performance 2. Additional research using 1 mg glucagon demonstrated it was as effective as 2 mg for biliary tract visualization 3.
Clinical Considerations
Route selection: Intravenous administration is preferred during ERCP because it provides faster onset of duodenal hypotonia. The lower IV dose (0.25-0.5 mg) achieves the same effect as the higher IM dose (1 mg) due to immediate bioavailability 1.
Safety profile: Recent large-scale data from 9,008 patients showed glucagon use during ERCP was associated with lower rates of gastrointestinal bleeding, post-ERCP pancreatitis, and mortality compared to procedures without glucagon 4. Importantly, hyperglycemia and hyperkalemia rates did not differ between groups, even in diabetic patients 4.
Common pitfall: Glucagon causes nausea and vomiting in some patients 5. Ensure airway protection measures are in place, particularly if the patient has received sedation.
Contraindications to avoid: Do not use glucagon in patients with pheochromocytoma (can cause hypertensive crisis), insulinoma (can cause paradoxical hypoglycemia), or known glucagon hypersensitivity 1.
Diabetic patients: While glucagon may cause transient hyperglycemia, this is generally well-tolerated during the brief ERCP procedure and does not require routine glucose monitoring in most cases 1.