Effect of mometasone furoate on early and late phase inflammation in patients with seasonal allergic rhinitis

Current perspective on eicosanoids in asthma and allergic diseases: EAACI Task Force consensus report, part I

Eicosanoids are biologically active lipid mediators, comprising prostaglandins, leukotrienes, thromboxanes, and lipoxins, involved in several pathophysiological processes relevant to asthma, allergies, and allied diseases. Prostaglandins and leukotrienes are the most studied eicosanoids and established inducers of airway pathophysiology including bronchoconstriction and airway inflammation. Drugs inhibiting the synthesis of lipid mediators or their effects, such as leukotriene synthesis inhibitors, leukotriene receptors antagonists, and more recently prostaglandin D₂ receptor antagonists, have been shown to modulate features of asthma and allergic diseases. This review, produced by an European Academy of Allergy and Clinical Immunology (EAACI) task force, highlights our current understanding of eicosanoid biology and its role in mediating human pathology, with a focus on new findings relevant for clinical practice, development of novel therapeutics, and future research opportunities.

Modulation of Allergic Inflammation in the Nasal Mucosa of Allergic Rhinitis Sufferers With Topical Pharmaceutical Agents

Allergic rhinitis (AR) is a chronic upper respiratory disease estimated to affect between 10 and 40% of the worldwide population. The mechanisms underlying AR are highly complex and involve multiple immune cells, mediators, and cytokines. As such, the development of a single drug to treat allergic inflammation and/or symptoms is confounded by the complexity of the disease pathophysiology. Complete avoidance of allergens that trigger AR symptoms is not possible and without a cure, the available therapeutic options are typically focused on achieving symptomatic relief. Topical therapies offer many advantages over oral therapies, such as delivering greater concentrations of drugs to the receptor sites at the source of the allergic inflammation and the reduced risk of systemic side effects. This review describes the complex pathophysiology of AR and identifies the mechanism(s) of action of topical treatments including antihistamines, steroids, anticholinergics, decongestants and chromones in relation to AR pathophysiology. Following the literature review a discussion on the future therapeutic strategies for AR treatment is provided.

Nasal cytology: Methodology with application to clinical practice and research

Nasal cytology is an easy, cheap, non-invasive and point-of-care method to assess nasal inflammation and disease-specific cellular features. By means of nasal cytology, it is possible to distinguish between different inflammatory patterns that are typically associated with specific diseases (ie, allergic and non-allergic rhinitis). Its use is particularly relevant when other clinical information, such as signs, symptoms, time-course and allergic sensitizations, is not enough to recognize which of the different rhinitis phenotypes is involved; for example, it is only by means of nasal cytology that it is possible to distinguish, among the non-allergic rhinitis, those characterized by eosinophilic (NARES), mast cellular (NARMA), mixed eosinophilic-mast cellular (NARESMA) or neutrophilic (NARNE) inflammation. Despite its clinical usefulness, cheapness, non-invasiveness and easiness, nasal cytology is still underused and this is at least partially due to the fact that, as far as now, there is not a consensus or an official recommendation on its methodological issues. We here review the scientific literature about nasal cytology, giving recommendations on how to perform and interpret nasal cytology.

Effects of Fluticasone Furoate Nasal Spray on Parameters of Eosinophilic Inflammation in Patients With Nasal Polyposis and Perennial Allergic Rhinitis

OBJECTIVES

Regulated on activation normal T cell expressed and secreted (RANTES) and eotaxin-2 have been postulated to be responsible for eosinophilia in chronically inflamed nasal mucosa. This study evaluated mucosal production of RANTES and eotaxin-2 in patients with perennial allergic rhinitis (PAR) and nonallergic and allergic form of chronic rhinosinusitis with nasal polyps (CRSwNP) before and after nasal corticosteroid treatment.

METHODS

Twenty patients with PAR, 20 nonallergic and 20 allergic CRSwNP patients, and 20 healthy controls were included. The RANTES and eotaxin-2 levels were measured in nasal secretion samples. The patients with chronic inflammation were treated with fluticasone furoate nasal spray for 2 weeks. Cytological examination and measurement of RANTES and eotaxin-2 in nasal fluid were performed before and after the treatment.

RESULTS

The levels of RANTES were higher in patients with PAR ( P < .05) and nonallergic ( P < .01) and allergic CRSwNP patients ( P < .001) compared to controls. Eotaxin-2 levels were higher in all 3 inflammation groups compared to healthy subjects ( P < .001). After the treatment, we found a significant decrease of RANTES and eotaxin-2 concentrations ( P < .001) in all 3 groups of patients.

CONCLUSION

The levels of RANTES and eotaxin-2 in nasal fluid could be reliable markers for assessing corticosteroid administration outcomes.

[The use of modern topical medications for the stepwise treatment of allergic rhinitis: the effectiveness and prospects for the further extension of their application]

The objective of the present work was to summarize the results of clinical studies designed to evaluate the effectiveness of 'Momate Rhino Advance' in the form of the nasal spray (based on the fixed combination of mometasone furoate and azelastine) that finds an increasingly wide application for the treatment of allergic rhinitis. The available data give evidence that this medication can be prescribed to the patients presenting with the severe and moderate form of allergic rhinitis. The treatment should be started with the use of the combined preparation and continued, after the adequate control of the clinical symptoms of allergic rhinitis is achieved, using 'Momate Rhino' during the next 2-4 weeks for the reliable management of the disease. It is concluded that the proposed strategy makes it possible to avoid the simultaneous application of multiple medications (polypragmasy) and thereby reduce the intake of medicines by the patients suffering from allergic rhinitis.

[The modern strategies for the treatment of allergic rhinitis]

The present literature review had the objective to analyze the published data concerning the effectiveness of intranasal administration of antihistamine preparations and intranasal glucocorticoids for the treatment of allergic rhinitis. Special emphasis is placed on the clinical significance and the further prospects for the application of a fixed combination of these medications including azelastineplusmometasonefuroateas the first choice therapy of moderately severe and severe manifestations of allergic rhinitis.

Mometasone furoate nasal spray for the treatment of asthma

INTRODUCTION

Asthma is a common respiratory disease characterized by airway inflammation, bronchoconstriction and airway hyperresponsiveness and symptoms such as coughing, wheezing, shortness of breath and chest tightness. Allergic rhinitis is a common comorbidity in asthma and glucocorticoids are the key stone in the treatment of both diseases. Mometasone furoate is a potent synthetic steroid with a very high receptor affinity and a low bioavailability and shown to be superior compared to other inhaled corticosteroids. It is not clear whether the use of mometasone furoate nasal spray (MFNS) is associated with an improvement in asthma control.

AREAS COVERED

This current paper reviews the current knowledge on the effect of mometasone furoate nasal spray in the treatment of asthma and includes clinical trials in which both subjective and objective outcomes are assessed.

EXPERT OPINION

To date, only few clinical studies have investigated the effect of nasal steroids in the treatment of asthma. The studies investigating the effect of MFNS report contradicting results, although the most well-designed study to answer this question finds no improvement in asthma control. Thus, it seems unlikely that asthma guidelines will be influenced by the current knowledge on the effect of MFNS in the treatment of asthma.

Intranasal steroids in the treatment of allergy-induced rhinorrhea

While nasal congestion has been identified as one of the most bothersome and prevalent symptoms of allergic rhinitis, it is underappreciated that many patients find rhinorrhea also to be bothersome. Rhinorrhea as a symptom of allergic rhinitis virtually never occurs alone; about 97% of patients with allergic rhinitis suffer from at least two symptoms, a finding that underscores the advantage of treating a broad range of symptoms with a single medication. Along with sneezing and nasal obstruction, rhinorrhea is a classic acute symptom of allergic rhinitis; it appears as a late-phase symptom as well. In this review, the characterization and epidemiology of rhinorrhea, the pathophysiology of rhinorrhea in allergic rhinitis, the roles played by mediators in early- and late-phase rhinorrhea, the prevalence and impact of this symptom, and the efficacy and safety of available treatment options are all discussed in context of relevant literature. A review of the clinical studies assessing the efficacy of intranasal corticosteroids (INS) for rhinorrhea is presented. Many clinical studies and several meta-analyses conclusively demonstrate that, in addition to being safe and well-tolerated, INS are more effective than other agents (including oral and intranasal antihistamines) across the spectrum of AR symptoms, including rhinorrhea and nasal congestion.

Intranasal Mometasone Furoate for Treatment of Allergic Rhinitis

Allergic rhinitis (AR) is a chronic nasal disease that affects the upper respiratory tract. This disorder is characterized by inflammation of the mucous membranes and it manifests with several nasal symptoms accompanied sometimes by non-nasal symptoms. Best therapy aims to prevent and improve the AR-clinical picture. Steroids have an important role in the treatment of AR. The development of steroids administrated directly on nasal mucosa has much reduced the systemic adverse affects associated with oral steroids therapy. Mometasone furoate aqueous nasal spray is a synthetic steroid assessed for intranasal use in the therapy of adults and children affected by AR. Such topical nasal steroid is an effective molecule improving clinical picture of AR and it is also approved as prophylactic therapy. In this article, apart from a careful description of its successful clinical use the authors review pharmacokinetic/pharmacodynamic profile, mechanism of action, safety, and efficacy of such steroid molecule.

Mometasone furoate nasal spray reduces the ocular symptoms of seasonal allergic rhinitis

BACKGROUND

Mometasone furoate nasal spray (MFNS), a potent intranasal corticosteroid with proved efficacy in relieving nasal allergic rhinitis symptoms, has demonstrated effectiveness in improving ocular symptoms associated with seasonal allergic rhinitis (SAR) in retrospective analyses.

OBJECTIVE

We sought to evaluate prospectively the efficacy of MFNS in reducing total ocular symptom scores (TOSSs) and individual ocular symptoms in subjects with SAR.

METHODS

Subjects 12 years or older (n = 429) with moderate-to-severe baseline symptoms were randomized to MFNS, 200 microg once daily, or placebo in this 15-day, double-blind, parallel-group study. Subjects evaluated morning instantaneous TOSSs and daily reflective TOSSs, total nasal symptom scores (TNSSs; both instantaneous TNSSs and reflective TNSSs, respectively), and individual ocular and nasal symptoms. Mean changes from baseline averaged over days 2 to 15 (instantaneous) and days 1 to 15 (reflective) were calculated. Quality of life was assessed by using the Rhinoconjunctivitis Quality of Life Questionnaire.

RESULTS

MFNS treatment yielded significant reductions from baseline versus placebo in instantaneous TOSSs (-0.34, P = .026, coprimary end point), instantaneous TNSSs (-0.88, P < .001, coprimary end point), reflective TOSSs (-0.44, P = .005), and reflective TNSSs (-1.06, P < .001). Significant decreases in all individual reflective ocular symptoms and instantaneous eye itching/burning and eye watering/tearing were observed for MFNS versus placebo (P < .05). Numeric improvements in instantaneous eye redness were seen but did not reach statistical significance. Improvements in Rhinoconjunctivitis Quality of Life Questionnaire total scores and individual symptom domains were achieved with MFNS treatment versus placebo (P < .001). MFNS was well tolerated.

CONCLUSION

This prospective study demonstrates that MFNS significantly reduces ocular symptoms in subjects with SAR.

Minimal persistent inflammation in allergic rhinitis: implications for current treatment strategies

Patients with allergic rhinitis have traditionally been placed into 'seasonal' and 'perennial' categories, which do not account for the subclinical inflammatory state that exists in many patients. In subjects with seasonal and perennial allergic rhinitis, even subthreshold doses of allergen have been found to cause inflammatory cell infiltration in the nasal mucosa, including increases in expression of cellular adhesion molecules, nasal and conjunctival eosinophilia, and other markers of inflammation, which do not result in overt allergy symptoms. This state - which has been termed 'minimal persistent inflammation'- may contribute to hyperreactivity and increased susceptibility to development of clinical symptoms as well as common co-morbidities of allergic rhinitis, such as asthma. Treating overt allergy symptoms as well as this underlying inflammatory state requires agents that have well-established clinical efficacy, convenient administration, potent anti-inflammatory effects and proven long-term safety, so that long-term continuous administration is feasible. Of the three major classes of commonly used allergic rhinitis medications - intranasal corticosteroids, anti-histamines, and anti-leukotrienes - intranasal corticosteroids appear to represent the most reasonable therapeutic option in patients who would benefit from continuous inhibition of persistent inflammation.

Inflammatory and oxidative stress biomarkers in allergic rhinitis: the effect of smoking

BACKGROUND

Accumulating evidence confirms the presence of pan-airway inflammation in allergic rhinitis patients. Smoking is known to affect the asthmatic airway inflammation. However, no study has evaluated the impact of smoking on airway inflammation of allergic rhinitis patients.

OBJECTIVE

The aim of the present study was to evaluate the impact of smoking on inflammatory and oxidative stress biomarkers in patients with seasonal allergic rhinitis, using non-invasive methods for sample collection.

METHODS

Forty patients with seasonal allergic rhinitis (20 smokers and 20 non-smokers) and 30 healthy subjects (15 smokers and 15 non-smokers) were recruited for the study during pollen season. All subjects were submitted to measurement of the fraction of exhaled NO (FeNO), exhaled breath condensate (EBC) collection, nasal lavage collection, pre- and post- bronchodilation spirometry and metacholine bronchial challenge testing. pH, leukotriene B(4) (LTB(4)) and 8-isoprostane were determined in EBC and nasal lavage samples.

RESULTS

Patients with allergic rhinitis presented higher LTB(4) and 8-isoprostane levels in nasal lavage (P<0.0001 for both comparisons), with no significant differences between smokers and non-smokers. Patients with allergic rhinitis also presented higher LTB(4) levels and lower pH in EBC (P<0.001 and P=0.004, respectively), with prominent differences between smokers and non-smokers (P<0.0001 and P=0.003, for LTB(4) and pH, respectively). A significant correlation between nasal lavage and EBC LTB(4) values was observed (r(s)=0.313, P=0.048).

CONCLUSIONS

Patients with allergic rhinitis present increased LTB(4) and 8-isoprostane in their nasal cavity, however, with no significant differences between smokers and non-smokers. In contrast, smokers with allergic rhinitis present higher LTB(4) levels and lower pH in EBC, suggesting that these patients may be more susceptible to the deleterious effects of smoking, compared with non-smokers.

Mometasone furoate: a review of its intranasal use in allergic rhinitis

Mometasone furoate (Nasonex) is a high-potency intranasal corticosteroid available for the treatment and/or prophylaxis of the nasal symptoms of seasonal allergic rhinitis (SAR) and perennial allergic rhinitis (PAR). In the EU, it is approved for use in patients aged > or =6 years and, in the US, it is approved as a treatment in patients aged > or =2 years and as prophylaxis in those > or =12 years of age.Extensive experience in both clinical trials and the clinical practice setting has firmly established the efficacy and good tolerability profile of intranasal mometasone furoate in children and adults with PAR or SAR. Thus, intranasal mometasone furoate is a useful first-line option for the treatment and prophylactic management of these conditions, including in children as young as 2 years of age in some countries and 6 years of age in others.

The role of leukotriene B(4) in allergic diseases

Leukotriene B(4) (LTB(4)) is a lipid mediator with potent chemoattractant properties and that is rapidly generated from activated innate immune cells such as neutrophils, macrophages, and mast cells. Elevated levels of LTB(4) have been reported in various allergic diseases and these levels have been related to disease activity and response to treatment. Recent studies using LTB(4) receptor-1 (BLT1) antagonists or BLT1-deficient mice have revealed that ligation of BLT1 by LTB(4) is important for the activation and recruitment of inflammatory cells including neutrophils, eosinophils, monocytes/macrophages, mast cells, dendritic cells, and more recently, effector T cells to inflamed tissues in various inflammatory diseases. The LTB(4)/BLT1 pathway appears to play an important role in the pathogenesis of severe persistent asthma, aspirin- and exercise-induced asthma, allergic rhinitis, and atopic dermatitis together with other mediators including cysteinyl leukotrienes, cytokines, and chemokines. LTB(4) production is in general resistant to corticosteroid treatment. In fact, corticosteroids can upregulate BLT1 expression on corticosteroid-resistant inflammatory cells such as neutrophils, monocytes, and effector memory CD8+ T cells. As a result, this corticosteroid-resistant LTB(4)/BLT1 pathway may contribute to the development of inflammation in allergic diseases that do not respond to the introduction of corticosteroids. Inhibition of this pathway has potential therapeutic benefit in various allergic diseases that have involvement of corticosteroid-insensitivity.

Efficacy of mometasone furoate nasal spray in the treatment of allergic rhinitis. Meta-analysis of randomized, double-blind, placebo-controlled, clinical trials

RATIONALE

Several randomized, double-blind, placebo-controlled clinical trials have demonstrated the efficacy of mometasone furoate nasal spray (MFNS) in the treatment of allergic rhinitis (AR) thus allowing for a meta-analysis to determine the overall treatment effect.

METHODS

A comprehensive search of the MEDLINE, LILACS, SCOPUS, and the Cochrane Library databases up to 31 October, 2007 was carried out. Randomized, double-blind, placebo-controlled, clinical trials evaluating the efficacy of MFNS in patients with AR compared to placebo were included. Total nasal symptom scores (TNSS), individual nasal symptoms, total non-nasal symptom scores (TNNSS) and nasal airflow were analysed as the standardized mean difference (SMD). Meta-analysis was performed with the random or the fixed effect models depending on heterogeneity, by using revman 5 software.

DATA SYNTHESIS

Sixteen of the 113 identified articles met the inclusion criteria. For MFNS efficacy on TNSS, 2998 participants were analysed: 1534 received MFNS and 1464 placebo. Mometasone furoate nasal spray was associated with a significant reduction in TNSS (SMD -0.49, 95% CI: -0.60 to -0.38; P < 0.00001; I(2) = 50.1%). A significant effect on SMD for nasal stuffiness/congestion (-0.41; 95% CI: -0.56 to -0.27), rhinorrhoea (-0.44; 95% CI: -0.66 to -0.21), sneezing (-0.40; 95% CI: -0.57 to -0.23) and nasal itching (-0.39; 95% CI: -0.53 to -0.25) was also demonstrated. Mometasone furoate nasal spray treated subjects also showed a significant reduction in TNNSS (-0.30; 95% CI: -0.43 to -0.18). The proportion of patients with adverse events was similar for MFNS and placebo (0.99; 95% CI: 0.81-1.20; P = 0.91).

CONCLUSIONS

This meta-analysis provides a level Ia evidence for the efficacy of MFSN in the treatment of AR vs placebo. Adverse events frequency was similar in both groups.

Allergen specific nasal challenge to latex in children with latex allergy: clinical and immunological evaluation

There are no data concerning the significance of allergen specific nasal challenge to latex (ASNCL) in the pediatric population and the effect of mometasone furoate nasal spray (MFNS), topic corticosteroid exerting a potent anti-inflammatory activity in children with latex allergic rhinitis. The aims of this study are: to investigate the clinical and immune pathological effects of ASNCL in children with latex allergy; to study the effects of MFNS pre-medication on the clinical and immune pathological effects of ASNCL in children with latex allergy. Thirteen children: 6 male and 7 female, mean (SD) age 9.6 (2.9) years, with latex allergy and seven children: 3 male and 4 female, mean (SD) age 9.9 (3.8) years, without latex allergy underwent ASNCL. Nasal symptoms were recorded, nasal lavage fluid was collected to measure tryptase, eosinophil cationic protein (ECP), interleukin-5, interferon-gamma levels, and spirometric test was performed for each patient without or with premedication with MFNS. ASNCL induced a clinical allergic response and increased tryptase levels only in children with latex allergy. No serious adverse events occurred after ASNCL. MFNS premedication reduced both tryptase and ECP levels only in children with latex allergy. ASNCL is a simple, reliable and useful tool to make or confirm the diagnosis of nasal symptoms due to latex; it allows us to study both clinical symptoms and local immunological changes. MFNS premedication before an ASNCL may prevent some immunological responses induced by ASNCL without clinical allergic modifications.

The time course of the bilateral release of cytokines and mediators after unilateral nasal allergen challenge

BACKGROUND

Late phase reactions after allergen challenge can be understood as a correlate of the inflammatory reaction in allergic rhinitis.

METHODS

To investigate which cytokines are involved in it and to dissect direct and indirect effects of nasal allergen challenge, we performed unilateral nasal allergen provocation with the disc method in 12 seasonal allergic volunteers. Symptom scores, nasal secretions and nasal airflow were quantified. In the secretions that were collected in the early phase and for 8 h after provocation, we measured histamine, and the cytokines interleukin (IL)-1beta, IL-8, IL-4, and the natural antagonist of IL-1beta, IL-1 receptor type 1 (IL-1Ra) using enzyme-linked immunosorbent (ELISA)-assays. Control challenges with diluent instead of allergen were performed in all subjects.

RESULTS

We demonstrated a bilateral increase in nasal secretion weights in the early and late phase. Histamine was significantly increased in the early and late phase in nasal secretions from both nostrils. IL-1beta increased in the late phase only, where it was also found on the unchallenged, contralateral side. Its antagonist IL-1Ra was found in very high quantities (1000-fold higher than IL-1beta) but demonstrated only marginal changes after provocation. IL-8 was increased in both nostrils early and late after challenge, whereas IL-4 was significantly elevated in the late phase.

CONCLUSIONS

We described the time course of mediator and cytokine release into nasal secretions after allergen challenge. We hypothesize that the observed indirect effects on the unchallenged, contralateral side can be at least partially attributed to neuronal reflexes.

Nasal allergies and beyond: a clinical review of the pharmacology, efficacy, and safety of mometasone furoate

Mometasone furoate nasal spray (MFNS; Nasonex, Schering-Plough Corporation, Kenilworth, NJ, USA) is an effective and well-tolerated intranasal corticosteroid approved for the prophylactic treatment of seasonal allergic rhinitis, and the treatment of perennial allergic rhinitis. MFNS is a potent molecule with a rapid onset of action and excellent safety and efficacy profiles. Having recently received approval for the treatment of nasal polyposis, data indicate that MFNS may also be effective in rhinosinusitis.

Features of mometasone furoate nasal spray and its utility in the management of allergic rhinitis

Mometasone furoate aqueous nasal spray (NS; Nasonex, Schering Corporation), is a synthetic corticosteroid approved for the prophylaxis and treatment of seasonal allergic rhinitis (SAR) and the treatment of perennial allergic rhinitis (PAR) in patients >or= 12 years of age, and for the treatment of SAR and PAR in children as young as 2 years of age. Studies demonstrate that mometasone furoate NS is a potent, clinically effective and well-tolerated intranasal corticosteroid with negligible systemic activity and which offers the convenience of once-daily dosing.

Intranasal corticosteroids for allergic rhinitis

Intranasal corticosteroids are accepted as safe and effective first-line therapy for allergic rhinitis. Several intranasal corticosteroids are available: beclomethasone dipropionate, budesonide, flunisolide, fluticasone propionate, mometasone furoate, and triamcinolone acetonide. All are efficacious in treating seasonal allergic rhinitis and as prophylaxis for perennial allergic rhinitis. In general, they relieve nasal congestion and itching, rhinorrhea, and sneezing that occur in the early and late phases of allergic response, with studies showing almost complete prevention of late-phase symptoms. The rationale for topical intranasal corticosteroids in the treatment of allergic rhinitis is that adequate drug concentrations can be achieved at receptor sites in the nasal mucosa. This leads to symptom control and reduces the risk of systemic adverse effects. Adverse reactions usually are limited to the nasal mucosa, such as dryness, burning and stinging, and sneezing, together with headache and epistaxis in 5-10% of patients regardless of formulation or compound. Differences among agents are limited to potency, patient preference, dosing regimens, and delivery, device and vehicle.

Mode of action of intranasal corticosteroids

The mode of action of intranasal corticosteroids (INCS) is complex. It is not known whether INCS penetrate the nasal mucosa or act on target cells; however, their low systemic activity supports the concept of local action on nasal mucosa. This local effect can nonetheless influence a variety of inflammatory cells and their mediators such as epithelial cells, lymphocytes, basophils, mast cells, and Langerhans cells. Corticosteroid-induced inhibition of immunoglobulin E-dependent release of histamine is a possible but unproven mode of action. Epithelial cells are an important target for corticosteroids, and INCS concentration is high at the epithelial surface. INCS may combine with the corticosteroid receptors in epithelial cells, which are then expelled into the airway lumen together with the dead epithelial cells or migrating inflammatory cells. A reduced influx of mediator cells may explain some of the effects of INCS on rhinitis symptoms, but it cannot explain all of the effects because INCS also reduce the early-phase sneezing and rhinorrhea after an allergen challenge outside the pollen season. In this situation, the number of surface mast cells/basophils is very low, as it is in the absence of allergic rhinitis. The mechanism by which INCS treatment of allergic rhinitis reduces itching, sneezing, and rhinorrhea, the characteristic symptoms of an early-phase response involving mast cell release of histamine, remains to be determined. Studies should be conducted to characterize the broad range of mechanisms by which INCS produce their therapeutic effects in allergic rhinitis.

Symptom provocation studies in psychiatric disorders: scientific value, risks, and future

Several lines of investigation have contributed to the increasing recognition of the biological basis of psychiatric disorders. Symptom provocation studies have made important contributions toward this. With the emergence of novel methodologies, the role of symptom provocation studies has come under increasing scrutiny and debate. The scientific contributions and risks of symptom provocation studies are discussed using the psychostimulant paradigm in schizophrenia research as the prototypical study. The application of studies in other areas of medicine that carry risks similar to those associated with symptom provocation studies, are also reviewed. The authors draw on the parallel of cardiac stress testing to highlight risks: benefits issues. Finally, the authors discuss the future of symptom provocation studies and emphasize that these studies will need to meet the highest scientific standards, ethical standards and safeguards.