Intranasal neuropeptide depletion using topical capsaicin for the control of symptoms in non-allergic, non-infectious perennial rhinitis (NANIPER)

Australian Journal of Oto-Laryngology, Oct 2002 by Havas, Thomas E, Taplin, Michael A

Objectives: This is a study to investigate the efficacy of self-application of topical capsaicin in the treatment of symptoms of nonallergic, non-infective perennial rhinitis. (NANIPER)

Materials and Methods: Forty patients were pseudo-randomized into two groups on an odds and evens basis and treated either with budesonide (Group One) or low-dose capsaicin (Group Two). Prior to treatment both groups completed a symptom sheet (visual analogue scale, VAS) 3 days prior to treatment and during the last 3 days of treatment. Symptom severity in various categories including headache, postnasal drip, rhinorrhea, nasal obstruction, sore throat and sneezing were assessed. Comprehensive statistical analysis of the data was performed.

Results and Conclusions: Decrease in nasal blockage was statistically significant in the group treated with capsaicin (p

Keywords: Capsaicin, Symptoms, Rhinitis

Introduction

Although a common clinical entity, non-allergic, noninfectious, perennial rhinitis (NANIPER) is a condition about which we have limited knowledge. It is unrelated to allergy, infection, structural lesion and/or systemic disease.1 The condition, characterized by symptoms of nasal obstruction, sneezing, rhinorrhea, postnasal drip and headache was hitherto known as vasomotor rhinitis. It is a diagnosis often made by exclusion and traditionally treatment of this condition, using medications specifically designed for either allergic rhinitis or cholinergic rhinitis, tends to be less successful for symptom amelioration than either of the two aforementioned groups.

Although the pathaphysiology of non-allergic rhinitis is unknown, several hypotheses have been put forward including;

1. Hyper-reactivity to thermal stimuli such as cold air with the release of inflammatory mediators.2 Although inflammatory cells appear to play a variable role in the majority of these patients,3 increased levels of LTC4 and PGD2 have been reported.4

2. Lacroix has shown that repeated administration of capsaicin, an active ingredient in red-hot peppers, derived from the genus Capsicum reduced nasal symptoms in patients with rhinosinusitis.5 This reduction was accompanied by a decrease in positive immuno-reactivity to calcitonin gene-related peptide (CGRP) in nasal biopsies.

This observation was consistent with the observation that capsaicin induced peptide depletion and specific degeneration of the small sensory non-myelinated C-fibres in the nasal mucosa of rodents.6 Several studies have been published showing that capsaicin desensitization may be an important therapeutic modality in NANIPER.7,8,9

In 1997, H. M. Blom et al published a placebocontrolled study in Clinical and Experimental Allergy suggesting that intranasal application of topical capsaicin was efficacious in symptom control in non-allergic, noninfectious perennial rhinitis.10

Although topical capsaicin has been difficult to obtain in Australia, Paedpharm have made capsaicin available in 3 doses. The senior author has previously been involved with Paedpharm undertaking clinical trials of several of their products, but does not have and never has had any direct financial dealings with or financial interest in the company. Full strength capsaicin (referred to as 3/3) delivers 0.654 micrograms per 70 microlitre dose. Two-thirds strength capsaicin (2/3) delivers 0.431 micrograms per 70 microlitre dose, and one-third (1/3) strength capsaicin delivers 0.216 micrograms per 70 microlitre dose. Capsaicin is available in a water-based aerosol with each squirt delivering 70 microlitres.

Prior to this study full-strength capsaicin had been used for over 3 years by the senior author to achieve neuropeptide depletion in patients with nasal polyposis, contact-point rhinitis and refractory non-infective nonallergic perennial rhinitis.

This pilot study was undertaken to see if sufficient symptomatic improvement could be obtained in a blinded study comparing the symptoms obtained from inhaled corticosteroid to a new regimen of administering capsaicin. The capsaicin in this study was administered initially at full dose (0.654 micrograms per 70 microlitre dose) and thereafter, self-administered weekly at the 1/3 strength dose (0.216 micrograms per 70 microlitre dose).

The reason for instigating this therapeutic regimen was that administration of full strength capsaicin requires pretreatment with topical anaesthesia and is significantly unpleasant. Low-dose capsaicin can be self-administered, does not require pre-treatment with local anaesthetic, and is well tolerated with minimal side effects. This makes it potentially an attractive alternative to medications already available to treat patients with non-allergic, non-infectious, perennial rhinitis.

Materials and Methods

Patients with perennial non-allergic rhinitis (IgE

As part of their physical examination, nasendoscopy was used to confirm the diagnosis of rhinitis. The presence of nasal septal deviation, nasal polyposis, rhinosinusitis and/or neoplasm was noted and those patients were excluded from the study, as were all smokers.