Efficacy and safety of superior laryngeal nerve block in neurogenic cough: A systematic review and meta-analysis.

backgroundNeurogenic cough is a chronic condition characterized by persistent coughing that is unresponsive to conventional treatments. It is thought to result from sensory neuropathy of the laryngeal nerves, leading to heightened cough reflex sensitivity. Current management strategies include neuromodulating medications and speech therapy, but these are often ineffective or associated with significant side effects. Superior laryngeal nerve (SLN) block has emerged as a minimally invasive alternative, hypothesized to modulate sensory feedback and disrupt maladaptive cough signaling pathways. This systematic review and meta-analysis aimed to assess the efficacy and safety of SLN block in the treatment of neurogenic cough.

methodsA comprehensive literature search was conducted using PubMed, Web of Science, and Scopus from inception to January 2025. Eligible studies included randomized controlled trials (RCTs) and observational studies evaluating SLN block for neurogenic cough. Outcomes analyzed included the Cough Severity Index (CSI), Leicester Cough Questionnaire (LCQ) scores, improvement rates, and incidence of serious adverse events. Data synthesis was performed using a random-effects model, and heterogeneity was assessed using the I² statistic.

resultsNine studies (eight retrospective and one RCT) with sample sizes ranging from 16 to 209 patients were included. SLN block resulted in a significant reduction in CSI scores (MD = -11.2, 95% CI: -15.32, -7.08) and a significant improvement in LCQ scores (MD = 2.23, 95% CI: 0.6, 3.85, p = 0.007). The intervention showed a high incidence of symptom improvement (effect estimate = 0.803, 95% CI: 0.722, 0.883) with a low rate of serious adverse events (effect estimate = 0.015, 95% CI: 0.0001, 0.03).

conclusionSLN block is a promising and safe intervention for neurogenic cough, demonstrating significant symptom relief and minimal adverse effects. However, further RCTs are needed to confirm long-term efficacy and establish standardized treatment protocols.