Topical corticosteroids applied with a squirt system are more effective than a nasal spray for steroid-dependent olfactory impairment

Objectives/Hypothesis: Oral corticosteroids may restore conductive olfactory dysfunction that has been defined as steroid-dependent olfactory loss, but the effect may be temporary. This study was designed to evaluate whether applying topical corticosteroids with a squirt system was more effective than using a nasal spray to maintain olfactory improvement following oral corticosteroids. Study Design: Prospective randomized trial enrolling 32 patients. Methods: Patients were enrolled if they had suffered from olfactory dysfunction for more than 3 months, and if their composite scores of odor threshold, discrimination, and identification scores in Sniffin' Sticks olfactory tests increased by more than six points after 1 week of oral corticosteroid treatment. A total of 32 patients were enrolled and randomized into two groups. All patients were treated with topical corticosteroids for 2 months using either the spray or squirt system, respectively. Results: Both measured and self-rated olfactory functions after 1 and 2 months of topical corticosteroid treatment were better in the squirt group than in the spray group. However, 2 months of topical corticosteroid treatment with the squirt system only partially maintained olfactory improvement. Conclusions: The application of topical corticosteroids with a squirt system was more effective than with a spray in maintaining olfactory improvement with oral corticosteroid treatment. Nevertheless, it only partially maintained the improvement so that topical corticosteroid treatment using a squirt system needs to be combined with intervals of short-term oral corticosteroids to treat steroid-dependent olfactory loss while avoiding the side effects of long-term oral corticosteroid use.