The reduction of rhinitis symptoms by nasal filters during natural exposure to ragweed and grass pollen

Abstract

This is the first clinical trial of a nasal filter. The results suggest it has potential for enhancing rhinitis management during acute allergen exposure.

Allergic Rhinitis and its Impact on Asthma (ARIA) 2008*

“…Rhinophototherapy is effective (1763), but more data using simpler equipment are needed. Nasal filters (1764) or pollen-blocker creams (1765) during natural exposure to ragweed and grass pollen can reduce nasal symptoms. An inert cellulose powder has been on sale in the UK since 1994 as a remedy for hay fever and was found to reduce symptoms of pollen rhinitis (1766).…”

The International Primary Care Respiratory Group (IPCRG) Research Needs Statement 2010

“…55,[109][110][111] Allergen avoidance can be effective for reducing the symptoms of allergic rhinitis, [112][113][114][115] though single interventions may be insufficient to control symptoms. 116 Non pharmacological measures with some efficacy include saline douches, 55,117-120 rhinophototherapy, 121 nasal filters, 122 pollen-blocker creams, 123 or cellulose powder. 124 Facemasks and eyeglasses may offer some protection, 125 and probiotics may influence symptoms of allergic diseases.…”

Nasal filters: a novel approach to tackling allergic rhinitis

“…The conceptual idea of moving the filtration into the nose itself, particularly when acute exposures to large particles such as pollens are involved, has obvious appeal. Further filtering of the nasal airflow might have a beneficial effect on allergic rhino-conjunctivitis, due to the nasal-ocular reflex [5].…”

“…In the open clinical study [8], the total Rhinoconjunctivitis Quality of Life Questionnaire symptoms scores over the day and night decreased significantly from 60 to 23 and 10, respectively, over 18 days; in the field study challenge [5], the major complex of rhinitis symptoms increased by approximately half in the placebo group and decreased by half in the active group (difference p = 0.0076); while in the laboratory challenge study [9], the mean daily but not maximum total nasal symptoms scores were reduced by 21% with active filter compared with placebo (p = 0.049). Most or all of the participants found the devices comfortable.…”

“…These include those homemade from foam [6], hand-made filters using a fine wire mesh [7], impaction-based filters [5], those with a spiral air path [8] and those with a thin layer of filter material supported by a flexible frame fitting inside the nasal cavity [9]. Clinical information is published for four; one of anecdotal experience [7]; one of an open clinical study [8]; and two of placebo-controlled, doubleblind trials using either natural [5] or laboratory pollen challenge [9], see FIGURE 1 as an example of such a filter.…”