On January 7, 2025, the U.S. Food and Drug Administration (FDA) issued a significant update concerning the safety of two respiratory syncytial virus (RSV) vaccines: Abrysvo, manufactured by Pfizer, and Arexvy, produced by GlaxoSmithKline. The FDA has mandated new safety labeling for both vaccines to include warnings about a potential increased risk of Guillain-Barré Syndrome (GBS), a rare but serious neurological disorder. This development stems from post-marketing observational studies that indicated an increased incidence of GBS within 42 days following vaccination with either Abrysvo or Arexvy. While the evidence does not establish a definitive causal link, it highlights the need for vigilance among healthcare providers and patients.