Intranasal Capsaicin Treatment for Non-Allergic Irritant Rhinitis

Double-Blinded Randomized Prospective Trial of Intranasal Capsaicin Treatment for Non-Allergic Irritant Rhinitis

The proposed study seeks to investigate the effect of intranasal capsaicin treatment in patient with Non-allergic irritant rhinitis (NAIR), as well as evaluate optical rhinometry (ORM) as a means to quantify symptomatic improvement in NAIR patients during and after treatment.

A study by Lambert et. al. (2012) was able to objectively identify patients with NAIR by intranasal capsaicin challenge followed by assessment with optical rhinometry. Studies have shown that capsaicin therapy can improve symptoms of patients historically identified with NAIR via visual analog scale (VAS) rating of symptoms and symptom surveys; however, there has been no study evaluating the capsaicin therapy on patients objectively identified as NAIR patients. Multiple studies have demonstrated that intranasal capsaicin can improve nasal symptoms of NAIR patients. Regarding the usage of capsaicin, there is a product on the market: Sinus Buster which has capsaicin as the active ingredient. Numerous research papers have evaluated the efficacy and safety of Sinus Buster for the treatment of congestion in non-allergic rhinitis patients. However, the diagnosis of NAIR in these previous studies was based primarily on history. In addition, the primary outcome in these studies was symptomatic without any objective evaluation. The goal of this study will be two-fold: with patients objectively identified as NAIR patients via the optical rhinometer, we will re-evaluate the therapeutic action of intranasal capsaicin on the management of rhinitic symptoms. We expect that the patients will show significant improvement in their symptoms. We will then use optical rhinometry as a means to objectively monitor changes in symptoms in NAIR patients. We expect that post treatment, patients will no longer have the positive response previously seen on intranasal capsaicin challenge before receiving treatment. We hope to be able to establish optical rhinometry as an objective measurement of symptom improvement for NAIR symptoms, along with the subjective patient surveys.

The capsaicin solution will be prepared by using the formula previously reported by Van Rijswijk et al; (0.1mmol/l) diluted in ethanol and 0.9% normal saline (19). Using the mucosal atomizer device (MAD), 0.8 milliliters (mL) will be delivered to each nasal cavity for a total of 24.4 ug per nasal cavity. 5 consecutive applications of capsaicin or placebo will be administered intranasally, with 1 hour between each application.

100 μL of 1% ethanol in 0.9% saline solution. 5 consecutive applications of capsaicin or placebo will be administered intranasally, with 1 hour between each application.

The Total Symptom Score (TSS) uses a visual analog scale (VAS) to assess typical nasal symptoms of non-allergic rhinitis (NAR), including sneezing, nasal irritation, nasal obstruction, and nasal congestion. The TSS is based on a commonly used rhinitis rating system recommended by the FDA for clinical trial studies on non-allergic rhinitis. 4 symptoms (sneezing, nasal irritation, nasal obstruction, and nasal congestion) are rated on a VAS ranging from 0 (none, no distress) to 10 (agonizing, unbearable distress). The TSS total score is the sum of the VAS score for each of the 4 symptoms, with the TSS total score ranging from 0 (none, no distress) to 40 (agonizing, unbearable distress).

The Total Symptom Score (TSS) uses a visual analog scale (VAS) to assess typical nasal symptoms of non-allergic rhinitis (NAR), including sneezing, nasal irritation, nasal obstruction, and nasal congestion. The TSS is based on a commonly used rhinitis rating system recommended by the FDA for clinical trial studies on non-allergic rhinitis. 4 symptoms (sneezing, nasal irritation, nasal obstruction, and nasal congestion) are rated on a VAS ranging from 0 (none, no distress) to 10 (agonizing, unbearable distress). The TSS total score is the sum of the VAS score for each of the 4 symptoms, with the TSS total score ranging from 0 (none, no distress) to 40 (agonizing, unbearable distress).

Change in Nasal Blood Flow as Indicated by Change in Maximal Optical Density Assessed by Optical Rhinometry

Optical rhinometry provides continuous measurement of blood flow in nasal vessels (via optical density measurements), which serves as an indirect assessment of nasal congestion. A greater decrease in optical density (OD) from baseline indicates less nasal blood flow and decreased congestion relative to baseline.

Change in Nasal Blood Flow as Indicated by Change in Maximal Optical Density Assessed by Optical Rhinometry

Optical rhinometry provides continuous measurement of blood flow in nasal vessels (via optical density measurements), which serves as an indirect assessment of nasal congestion. A greater decrease in optical density (OD) from baseline indicates less nasal blood flow and decreased congestion relative to baseline.

Inclusion criteria: Non-allergic irritant rhinitis (NAIR) patients as defined by history (symptoms of nasal congestion, rhinorrhea, nasal itching or sneezing upon exposure to nasal irritants) Patients with positive optical rhinometer (ORM) response with intranasal challenge with 0.5 millimolar (mM) capsaicin as described by Lambert et al 2012 Confirmed negative skin prick test to common allergens (which rules out allergic rhinitis) Exclusion Criteria: History of sinonasal surgery Chronic rhinosinusitis Inflammatory or granulomatous diseases Asthma Allergic rhinitis Immunocompromised state Radiation to the head and neck Intranasal steroid use >4 wks Intranasal or systemic antihistamine x 3 days Intranasal or systemic decongestants x 3 days