Evaluating Effects of Preservative-Containing Saline Solution on Pain Perception During Botulinum Toxin Type-A Injections at Different Locations: A Prospective, Single-Blinded, Randomized Controlled Trial

Pain is a side effect of botulinum toxin type-A (BTX-A) injections. The efficiency of the preservative-containing saline solution used as the “dilution solution” for controlling the pain felt during multiple injections in different areas has been investigated by a prospective, randomized, single-blinded, controlled study. A total of 93 patients were divided into three groups for the study. All the patients were given BTX-A. Of these 93 patients, 60 received injections in the upper face, 15 in the neck, and 18 in the axillary regions. The visual analog scale (VAS), a single-dimension pain intensity rating scale, was used to evaluate pain perception. The average VAS values for pain sensation experienced by the groups were 1.2 of 10 points for the upper face area in the experimental group (n = 60) and 4.5 point for the control group. In the neck region (n = 15), the respective scores were 0.6 in the experimental group and 3.9 in the control group. Finally, in the axillary region (n = 18), the respective values were 0.9 and 5.1. The authors conclude that the preservative-containing saline solution significantly decreased pain perception during BTX-A injections (p = 0.000).