Catamenial Loss of Botulinum Toxin Efficacy Successfully Managed with Tamoxifen: A Case Report

Video 1: Baseline response to botulinum toxin type A (BoNT-A) injection before menses showing satisfactory aesthetic response with visible reduction in dynamic rhytids in the glabellar, frontal, and lateral canthal regions. Video 2: Reduced efficacy of BoNT-A during the perimenstrual phase demonstrating recurrence of dynamic rhytids and reduced neuromodulatory effect, temporally associated with the menstrual cycle. Video 3: Restoration of BoNT-A efficacy following initiation of tamoxifen demonstrating improved and sustained neuromodulatory response therapy at month 3 following her BoNT-A session.