Introduction Patients rarely accept colonoscopy without anxiety because the procedure is commonly associated with significant pain (1). Different agents were investigated to increase patient comfort and technical performance of colonoscopy with variable success and adverse events profiles (2). Diclofenac inhibited visceral pain signals on colonic stretching in animal studies (3).
Method We have conducted a single-centre randomised study to evaluate the analgesic effect of diclofenac versus placebo in patients undergoing unsedated colonoscopy. Patients were randomised to receive 100 mg of diclofenac (Group 1) or placebo (Group 2). We used a 10-point VAS scale for pain. Mann-Whitney test was used to compare mean pain index and time to discharge. Spearman’s test was used for correlation between caecal intubation rates and pain.
Results We recruited a total of 88 patients divided into 2 groups: 43 (48.9%) in intervention group and 45 (51.1%) into placebo group. Baseline characteristics of patients did not differ significantly. There was no difference between groups in pain during colonoscopy (Mann-Whitney; Z=−0.84; p=0.40) or in grading of colonoscopy experience (1–10 scale) (Mann-Whitney; Z=−0.99; p=0.32), or number of patients that would repeat colonoscopy. There wasn’t any significant correlation between caecal intubation time and pain scale values (Spearman’s r=0.17; p=0.20). A significant correlation between caecal intubation time and pain scale values was found in placebo group (Spearman’s r=0.37; p=0.04) but not in intervention group (Spearman’s r=−0.08; p=0.71). Two lethal outcomes were recorded, both in the placebo group (4.4%; p=0.50%). Time to discharge in days was also not significantly different (Mann Whitney; Z=−0.18; p=0.85).
Conclusion There does not seem to be an effect of diclofenac on pain during unsedated colonoscopy compared with placebo.
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Disclosure of Interest None Declared
- visceral pain