Objectives: To test the hypothesis that the chemical content of lignocaine gel is the cause of urethral pain during its instillation into the urethra.
Methods: A prospective, double blind study was designed to test whether plain aqueous gel caused less delivery discomfort in the male urethra than 2% lignocaine hydrochloride gel (Instillagel). 100 consecutive, consenting male patients attending for flexible cystoscopy were recruited and randomised to receive 11 ml of 2% lignocaine hydrochloride gel or 11 ml of plain aqueous gel. Upon receiving the gel into the urethra, the patient was asked to score any associated discomfort by using a horizontal, 100mm, non-graphical, visual analogue scale. Statistical comparison between the groups was made using the non-parametric Mann-Whitney U-test.
Results: Statistical analysis by Mann-Whitney U-test showed a significant reduction in urethral delivery discomfort in those patients receiving plain gel compared to those receiving 2% lignocaine hydrochloride gel (p=0.039).
Conclusions: This current study has shown that plain aqueous gel causes significantly less delivery discomfort in the male urethra than 2% lignocaine hydrochloride gel (Instillagel).