Safety and tolerability of surfactant nasal irrigation

Background: Abnormal mucus composition and bacterial biofilms are thought to contribute to the pathophysiology of rhinosinusitis. Addition of a mucoactive surfactant to saline irrigation solution has been hypothesized to address these factors. We evaluated the safety and tolerability of a reformulated surfactant in a sample of normal subjects.

Methods: A total of 33 volunteers were randomly assigned to receive either surfactant solution or buffered saline at baseline in a controlled crossover study design. Each subject underwent rhinoscopic exam and in-office smell testing via the 40-question smell identification test (SIT). Those with non-normosmic results or active rhinitis symptoms were excluded. Subjects were instructed to irrigate twice daily with the selected solution for 1 week while keeping a daily diary. For week 2, treatment was stopped. During week 3, each group switched to the other treatment. Exam, SIT, and degree of congestion were assessed after each phase.

Results: Use of surfactant led to a marginal reduction in mean SIT score of 1.5 points, which was statistically significant (p = 0.012). A clinically meaningful reduction in SIT score, defined as ≥4 points, was observed in 18% (6/33) of subjects after surfactant vs 3% (1/33) after saline (p = 0.046). During the surfactant phase, moderate or severe congestion was reported in 29% (8/28) of subjects completing the diary. In contrast, only 6% (2/32) of subjects reported moderate congestion after the saline phase (p = 0.021).

Conclusion: In normal volunteers, surfactant nasal irrigation may be associated with tolerability issues due to congestion. A subset may experience reduction in olfactory acuity that appears reversible.