Fentanyl administered by sublingual tablet was not found to be an effective pain management option for patients undergoing colonoscopy, according to the results from a study published in Scientific Reports. Despite the cost-effectiveness of using a tablet instead of intravenous administration, no difference in pain intensity was observed in patients receiving treatment with a fentanyl tablet compared with placebo.
Although numerous drugs are used to prevent and manage pain during a colonoscopy, the optimal drug and dose remain unclear. Investigators therefore conducted a randomized, double-blind, placebo-controlled study to assess the feasibility of a transmucosal sublingual fentanyl tablet for pain management during colonoscopy.
Patients undergoing diagnostic or therapeutic colonoscopy were recruited from a hospital in Finland between 2012 and 2018. Participants were randomly assigned to receive either sublingual fentanyl 100 μg or placebo. Both drugs were available in tablet form and administered 10 minutes before the procedure.
The primary outcome was average pain intensity during and after the colonoscopy. Pain was described by patients on a numerical rating scale. Patients were also asked to rate their overall satisfaction with the procedure prior to discharge. Results were compared between the fentanyl and placebo groups.
The final study group comprised 144 patients, among whom 72 received fentanyl and 72 received placebo. More than half (54%) of the participants were men. Mean age was 59.9 +/- 13.5 years in the placebo group and 57.9 +/- 13.6 years in the fentanyl group.
No substantial between-group differences in pain intensity or degree of sedation were reported. Median pain intensity in the fentanyl group was 4.5 out of a possible 10 compared with 5 in the placebo group (P =.852). Median procedure duration was 15 (range, 5-40) minutes in the placebo group and 20 (range, 5-50) minutes in the fentanyl group. Oxygen saturation levels and respiratory rates were also comparable between study arms. Postprocedural interviews revealed no difference in satisfaction levels between groups.
Based on these results, the investigators did not recommend a transmucosal sublingual fentanyl tablet for pain management in patients undergoing colonoscopy. Although the 100-μg fentanyl tablet was not associated with any adverse events, pain levels of the fentanyl group were comparable to those of the placebo group.
As study limitations, the investigators cited the long recruitment period and the short interval between fentanyl administration and start of the procedure. Fentanyl dose timing may affect bioavailability and pain management.
“Our results indicate that a single sublingual low-dose opioid is not an ideal premedication for patients having a colonoscopy,” the investigators wrote. “Current ambulatory practice requires fast patient turnover, an efficient and short-acting analgesic, and the rapid discharge of patients. It remains to be elucidated whether a combination of fentanyl and oral benzodiazepine would be more effective, equally safe, and able to eliminate the need for deeper intravenous sedation during a colonoscopy.”
Fihlman M, Karru E, Varpe P, et al. Feasibility of a transmucosal sublingual fentanyl tablet as a procedural pain treatment in colonoscopy patients: a prospective placebo‑controlled randomized study. Sci Rep. Published online December 10, 2020. doi:10.1038/s41598-020-78002-0