Background: Previous studies on the routine use of glucagon in colonoscopy have produced conflicting results.
Methods: Two separate studies were performed. In one study (Study 1), 80 consecutive patients were randomized after cecal intubation to receive 1 mg glucagon (n = 41) or placebo (n = 39), intravenously, in double-blind fashion. In a second study (Study 2) 90 sedated patients undergoing colonoscopy were randomized to receive 1 mg glucagon (n = 46) or placebo (n = 44), intravenously, just before colonoscope insertion. In each study, colonoscope insertion and withdrawal time, therapeutic intervention time, the presence and severity of colonic spasm, colonoscopy yield, and side effects were recorded.
Results: Mean withdrawal time in Study 1 was similar in those receiving glucagon (6.85 min) and in those receiving placebo (6.92 min). Mean insertion time in Study 2 (5.07 min) was identical between groups. Spasm scores and colonoscopy yield did not differ between glucagon and placebo in either study. There was a trend toward more side effects (nausea and vomiting) with glucagon in Study 1. Glucagon did not facilitate insertion or withdrawal in the subset of patients with diverticulosis.
Conclusions: Routine use of intravenous glucagon in a dosage of 1 mg does not facilitate colonoscopy by experienced examiners.