The goal of the proposed project is to assess the efficacy, safety, and patient experience of budesonide administered via the NasoNeb system for medical management of CRS. The authors propose a randomized controlled trial of nebulized budesonide via the NasoNeb compared against budesonide lavage.

Chronic rhinosinusitis is primarily an inflammatory disorder affecting up to 1 in 8 individuals and causing economic burden of greater than 13 billion USD. The NasoNeb is FDA approved for the nasal administration of medications; however, it has been scarcely studied in the existing literature. Many patients are intolerant of or non-compliant with other modalities of nasal steroid administration, and the NasoNeb represents a potential new treatment method for these patients.

Participants will be provided with either a NasoNeb machine or NeilMed lavage bottle, and a prescription for a 42-day supply of 0.5 mg budesonide packets, to be used twice daily. For the NasoNeb, each dose will be dissolved in 10 mL saline with 5 mL nebulized solution being applied to each nasal cavity. This dose was chosen given the historical evidence of efficacy of budesonide 0.5mg daily application via saline lavage.

For the lavage, each budesonide dose will be dissolved in 240 mL saline. Participants will be shown proper use of the NasoNeb machine or lavage bottle at the time of enrollment and be given written instructions with links to video tutorials.

Inclusion Criteria:

• Age 18 or older that meet diagnostic criteria for CRS with or without polyposis as documented by their recruiting physician.
• Diagnostic criteria for CRS will be defined according to EPOS criteria of >12 weeks of 2 of the following subjective symptoms: nasal blockage or obstruction, rhinorrhea, hyposmia, or facial pain/pressure AND objective evidence of CRS on either nasal endoscopy or CT scan

Exclusion Criteria:

• Patients who have previously undergone sinus surgery
• Severe polyposis; defined as Lund Kennedy endoscopy score greater than 1
• Patients who are currently using or who have previously used biologic medications for their nasal polyps. These medications include: dupilumab, omalizumab, mepolizumab, tezepelumab, or depemokimab
• Inability to complete surveys in English
• known comorbid mucociliary disease
• known adrenal disease or other HPA dysfunction
• patients taking oral corticosteroids for other medical conditions
• oral antibiotic administration within 2 weeks of study participation
• a baseline SNOT-22 score less than 9, due to inability to achieve the MCID

Study coordinators will be blinded to treatment arm during data analysis.