Evaluation of the anti-peristaltic effect of glucagon and hyoscine on the small bowel: comparison of intravenous and intramuscular drug administration

Purpose To evaluate prospectively duration and effectiveness of aperistalsis achieved by glucagon(GLU) or hyoscine N-butylbromide(HBB) following various administration routes. Materials and methods Six volunteers underwent Magnetic Resonance Imaging (MRI) after standardized oral preparation in random order five separate MR examinations with both spasmolytic agents (HBB intravenous(i.v.) or intramuscular(i.m.), GLU i.v. or i.m., and a combined scheme). The MR protocol included a sagittal 2D cross-section of the small bowel with a temporal resolution of 0.55 s acquired over 60 to 90 min. To quantify bowel motility, small bowel cross-sectional areas were summated over time. Results The anti-peristaltic i.v. effects of HBB and glucagon started on average after 85 s/65 s and ended after 21 min/23.3 min, respectively. By comparison, the anti-peristaltic effects of i.m. HBB and glucagon started significantly later 5.1/11.6 min ( = 0.001; Wilcoxon signed ranks test) and lasted for 17.7/28.2 min with greater inter-individual differences ( = 0.012; Brown-Forsythe test). The combined scheme resulted in a rapid onset after 65 s with effect duration of 31 min. Conclusion Anti-peristaltic effects on the small bowel are drug dependant, i.e., their onset is faster and more reliable when administering i.v. than i.m.. Combining i.v. GLU with i.m. HBB provides an early onset of effect, sustained spasmolysis and the highest degree of motility impairment. Key Points Anti-persitaltic agents are widely used before various diagnostic procedures of the abdomen. The combination of iv-glucagon with im-hyoscine provides reliable spasmolysis with early onset. Intravenous spasmolysis is more reliable compared to intramuscular administration. Intravenous glucagon has a prolonged spasmolytic effect compared to intravenous hyoscine.