Background: Flexible rectosigmoidoscopy is an easy and accessible exam to diagnose
distal colon diseases, although many patients refuse to undergo it due to pain and discomfort during
the procedure. Studies show that the application of local lidocaine, as an analgesic has no effect
on pain relief in patients undergoing rectosigmoidoscopy. The current study aims at comparing the
effects of diltiazem gel, an antispasmoic drug with local pain-reducing effects, with lidocaine gel in
patients undergoing flexible rectosigmoidoscopy.
Materials and Methods: The current double-blinded, randomized, clinical trial was performed to
compare the effect of two topical drugs, lidocaine and diltiazem, on pain relief in patients undergoing
rectosigmoidoscopy. A total of 80 patients who were potential candidates for rectosigmoidoscopy
were enrolled in the study after obtaining the informed consent and then randomly assigned
to one of the lidocaine gel (2 mL) or diltiazem gel (2 mL) group, 10 minutes prior to rectosigmoidoscopy.
The level of pain in the patients during the procedure was measured using the visual analogue
scale (VAS) and the results were recorded. The data were analyzed using paired samples ttest
and independent t-test as well as analysis of covariance (ANOVA) with SPSS version 18. P-value
<0.05 was considered the level of significance.
Results: Of 80 patients, 35 (43.75%) were male and 45 (56.25%) female. The mean age and body
mass index (BMI) of the patients were 51.45 ± 15.21 years and 25.95 ± 7.47 kg/m2, respectively,
and there was no significant difference between the groups. The most frequent indications for rectosigmoidoscopy
were abdominal pain (46.3%) and rectorrhagia (31.3%). The mean VAS score for
pain reported by the patients in the lidocaine and diltiazem groups was 3.97 ± 2.89 and 2.60 ± 2.36,
respectively. The VAS score for pain in the diltiazem group was significantly lower than lidocaine
group (P = 0.023).
Conclusion: The application of local diltiazem gel around the anus, in spite of no side effects, can
effectively reduce the pain and discomfort in patients during rectosigmoidoscopy. Iranian Registry
of Clinical Trials (Reg. No 31055).