Introduction:Our objective was to compare the effect of rectal misoprostol (Cytotec) versus rectal hyoscine-n-butyl bromide (Buscopan) on patients undergoing hysteroscopy. We hypothesised that HBB may have a role in cervical priming. Material and methods:This trial was conducted at Bezmialem Vakif University Hospital. Women of reproductive age between 18-50 years who were scheduled for operative hysteroscopy indicated by type 1 submucous myoma or endometrial polyps were recruited for the study. Ninety patients were divided randomly into three groups. Group 1 received placebo treatment. Group 2 received rectal 200 mcg misoprostol and Group 3 received rectal 20 mg hyoscine-n-butyl bromide two hours before the procedure. Procedures were performed using a bipolar 26 F (9 mm) continuous-flow rigid resectoscope with a 30 degrees lens. The outcome measures included cervical dilation width and time, ease of cervical dilation, procedure time and operative complications. Postoperative self-rated pain was assessed one hour after the procedure. Results:Thirteen patients (43. 3%) in the placebo treatment group, 11 patients (36.7%) in the misoprostol group and four patients (13.3%) in the hyoscine-n-butyl bromide group needed analgesics postoperatively (p = .02). The mean duration of cervical dilation time was longest in Group 1 and shortest in Group 3, however this difference did not reach statistical significance (p=.11). There was no difference with regard to other studied parameters. Summary:HBB reduced the need for pain medication compared to placebo. Larger studies are needed to further investigate the role of HBB in facilitating pre-operative cervical priming.