BackgroundFacial wrinkles, caused by aging and repetitive muscle contractions, are commonly treated with botulinum neurotoxin type A (BoNT-A). However, excessive toxin diffusion can cause side-effects like muscle weakness.ObjectivesThis study aimed to compare the diffusion, efficacy, and safety of letibotulinum toxin A with two other BoNT-A products for treating forehead wrinkles.MethodsIn a double-blind, randomized, split-face controlled trial, 20 participants with moderate-to-severe horizontal forehead wrinkles received letibotulinum toxin A on one side and prabotulinum or onabotulinum toxin A on the other. The primary outcome was diffusion profile assessed via anhidrosis area (iodine-starch test at 2 weeks); secondary outcomes included wrinkle reduction, assessed by photographic analysis, and safety.ResultsResults show that letibotulinum toxin A exhibited diffusion patterns and wrinkle-reduction efficacy comparable to the control products. No statistically significant differences were observed be-tween the groups for the primary or secondary outcomes.ConclusionLetibotulinum toxin A is a safe, effective alternative for wrinkle treatment, potentially minimizing excessive diffusion risks and related side effects, making it a valuable addition to available treatment options.