Intranasal Insulin and Budesonide Combination Films for Treatment of Anosmia: Randomized Clinical Trial

Background : Smell is strongly related to quality of life. Therefore, anosmia has been considered one of the serious health conditions. Different treatment regimens were used as auxiliary therapy for improving olfaction but were not approved as final treatments. Recently, intranasal insulin has been developed as a treatment of anosmia. The purpose of this study is to present a more specific, effective, and safe treatment for anosmia, by adding strong steroid to insulin in the same film. This study was conducted on 40 patients with post-viral anosmia. Methodology was built-in multiple steps: study compatibility between steroid and insulin, preparation and characterization of intranasal films, and clinical assessment. Patients were randomly allocated into 2 parallel groups; intervention and placebo groups, both underwent endoscopic placement of intranasal insulin-budesonide combination films and saline films into the olfactory cleft, respectively. The procedure was performed for 8 sessions with 2 weeks interval. Results : The results of compatibility and film characterization showed compatible combination in addition to flexible, homogenous, and controlled-release films. Clinical assessment showed significant improvement of intervention group compared to control group in both butanol test and olfactory discrimination test (p value 0.004 in the second visit and P<0.001 in the third visit, respectively). Conclusion : According to our results, it can be concluded that a combination of anti-inflammatory steroids and growth factor elevator as insulin can be used as safe and effective combination for smell restoration.