The role of routinely given hyoscine-N-butylbromide in colonoscopy: a double-blind, randomized, placebo-controlled, clinical trial

Hyoscine-N-butylbromide (HBB) has been proposed to ease colonoscopy and improve mucosal visualization, yet the results from previous studies are conflicting. In our prospective, double-blind, placebo-controlled, randomized study we aimed at evaluating whether routine administration of HBB, before and during colonoscopy, ease the procedure or increase the detection rate for polyps.

One hundred fifty outpatients scheduled for an elective colonoscopy were randomized to receive intravenous injections of either 10 mg hyoscine-N-butylbromide or saline before insertion and at cecum. Patient tolerance and technical ease of colonoscopy were evaluated by visual analogue scale (VAS). Procedure times were recorded. Number of detected polyps per patient was evaluated as well. Heart rate was monitored with a pulse oximetry.

HBB did not improve patient tolerance or technically ease the procedure as evaluated by VAS. However, HBB led to faster ileal intubation (1.5 vs 2.0 min, p < 0.001) and shorter total procedure time (22.0 vs 24.0 min, p = 0.03). Patients who received HBB also needed less often external abdominal pressure (48.6 vs 66.7%, p = 0.03). HBB did not improve polyp detection rate (0.89 vs 0.91, p = 0.90). HBB induced a significant rise in heart rate (p < 0.001) and more often tachycardia (17.6 vs 0%, p < 0.001).

Routine administration of HBB before and during colonoscopy yields only limited improvement in the technical performance of the examination compromised by high incidence of tachycardia.