Botulinum toxin type A improves nasal symptoms in refractory allergic rhinitis with SMD -2.07 at 4 weeks

PURPOSE OF REVIEW: Botulinum toxin type A (BTX-A) is emerging as a promising intervention for refractory allergic rhinitis. This study evaluates its effectiveness in treating refractory allergic rhinitis. RECENT FINDINGS: The primary outcome was total nasal symptom score (TNSS), while secondary outcomes included individual nasal symptom scores, quality of life (QOL), and adverse effects. Five trials involving 187 patients (mean age: 31.8 years) were included. BTX-A significantly improved TNSS at 4 weeks [SMD -2.07, 95% confidence interval (95% CI) -3.58 to -0.56; P  < 0.001] and 12 weeks (SMD -2.42, 95% CI -4.22 to -0.62; P  < 0.001). Neither comparison of BTX-A with triamcinolone injection nor oral cetirizine showed a significant difference in TNSS (SMD - 0.51, 95% CI -1.25 to 0.24; P  = 0.18 and SMD 0.50, 95% CI -0.07 to 1.06; P  = 0.08, respectively). In the BTX-A group, significant improvements were observed in rhinorrhea (SMD -2.18, 95% CI -3.74 to -0.62; P  < 0.001), sneezing (SMD -1.88, 95% CI -2.60 to -1.15; P  < 0.001), and itchiness (MD -1.57, 95% CI -2.45 to -0.69; P  < 0.001) at 4 weeks, with these effects persisting up to 12 weeks. No serious adverse events occurred following BTX-A administration. SUMMARY: BTX-A shows promise as an adjunctive therapy for refractory allergic rhinitis.