Stellate ganglion block causing reproducible improvement of allergic rhinitis and asthma: a case report.

Introduction: Stellate ganglion block (SGB) is hypothesized to influence immunologic and physiologic processes through autonomic modulation. Though similar effects of SGB on atopic disease have been intermittently observed over the past century, methodological concerns limit the internal and external validity of these prior efforts. Objectives: To describe a case of simultaneous and reproducible improvement in allergic rhinitis and asthma after SGB, and to contextualize this observation within the existing literature. Methods: A 35-year-old woman with Complex Regional Pain Syndrome (CRPS) following a radial head fracture underwent SGB as a part of routine CRPS management. Her incidentally-observed changes in allergic rhintis and asthma were assessed longitudinally using validated clinical outcome measures in a retrospective fashion. Results: The patient demonstrated improvement of her allergic rhinitis and asthma after SGB, exceeding MCID thresholds for meaningful clinical improvement of each condition. These benefits persisted for 9 months before a partial recurrence of her atopic airway disease. A second SGB was able to reproduce these improvements, again exceeding MCID thresholds for both allergic rhinitis and asthma. Conclusions: SGB's effects on atopic disease warrant reappraisal of SGB as a potential adjunct for atopic airway disease, particularly in light of recent experimental evidence suggesting that SGB may exert an immunomodulatory effect. This case therefore highlights a meaningful gap in the literature and underscores the need for systematic investigation of SGB as a potential adjunctive treatment for atopic airway disease.