Risk of first-generation H(1)-antihistamines: a GA(2)LEN position paper

Antihistamine use in children

This review provides an overview of the use of antihistamines in children. We discuss types of histamine receptors and their mechanism of action, absorption, onset and duration of action of first-generation and second-generation H(1)-antihistamines, as well as elimination of H(1)-antihistamines which has important implications for dosing in children. The rationale for the use of H(1)-antihistamines is explored for the relief of histamine-mediated symptoms in a variety of allergic conditions including: non-anaphylactic allergic reactions, atopic eczema (AE), allergic rhinitis (AR) and conjunctivitis, chronic spontaneous urticaria (CSU) and whether they have a role in the management of intermittent and chronic cough, anaphylaxis, food protein-induced gastrointestinal allergy and asthma prevention. Second-generation H(1)-antihistamines are preferable to first-generation H(1)-antihistamines in the management of non-anaphylactic allergic reactions, AR, AE and CSU due to: their better safety profile, including minimal cognitive and antimuscarinic side effects and a longer duration of action. We offer some guidance as to the choices of H(1)-antihistamines available currently and their use in specific clinical settings. H(1)-antihistamine class, availability, licensing, age and dosing administration, recommended indications in allergic conditions and modalities of delivery for the 12 more commonly used H(1)-antihistamines in children are also tabulated.

Optimal management of allergic rhinitis

Allergic rhinitis (AR), the most common chronic disease in childhood is often ignored, misdiagnosed and/or mistreated. Undertreated AR impairs quality of life, exacerbates asthma and is a major factor in asthma development. It can involve the nose itself, as well as the organs connected with the nose manifesting a variety of symptoms. Evidence-based guidelines for AR therapy improve disease control. Recently, paediatric AR guidelines have been published by the European Academy of Allergy and Clinical Immunology and are available online, as are a patient care pathway for children with AR and asthma from the Royal College of Paediatrics and Child Health. Management involves diagnosis, followed by avoidance of relevant allergens, with additional pharmacotherapy needed for most sufferers. This ranges, according to severity, from saline sprays, through non-sedating antihistamines, oral or topical, with minimally bioavailable intranasal corticosteroids for moderate/severe disease, possibly plus additional antihistamine or antileukotriene. The concept of rhinitis control is emerging, but there is no universally accepted definition. Where pharmacotherapy fails, allergen-specific immunotherapy, which is uniquely able to alter long-term disease outcomes, should be considered. The subcutaneous form (subcutaneous immunotherapy) in children has been underused because of concerns regarding safety and acceptability of injections. Sublingual immunotherapy is both efficacious and safe for grass pollen allergy. Further studies on other allergens in children are needed. Patient, carer and practitioner education into AR and its treatment are a vital part of management.

Phenotypes and endotypes of rhinitis and their impact on management: a PRACTALL report

Rhinitis is an umbrella term that encompasses many different subtypes, several of which still elude complete characterization. The concept of phenotyping, being the definition of disease subtypes on the basis of clinical presentation, has been well established in the last decade. Classification of rhinitis entities on the basis of phenotypes has facilitated their characterization and has helped practicing clinicians to efficiently approach rhinitis patients. Recently, the concept of endotypes, that is, the definition of disease subtypes on the basis of underlying pathophysiology, has emerged. Phenotypes/endotypes are dynamic, overlapping, and may evolve into one another, thus rendering clear-cut definitions difficult. Nevertheless, a phenotype-/endotype-based classification approach could lead toward the application of stratified and personalized medicine in the rhinitis field. In this PRACTALL document, rhinitis phenotypes and endotypes are described, and rhinitis diagnosis and management approaches focusing on those phenotypes/endotypes are presented and discussed. We emphasize the concept of control-based management, which transcends all rhinitis subtypes.

Management of urticaria: not too complicated, not too simple

In spite of being an old disease and apparently easy to diagnose, chronic spontaneous urticaria (CSU) is still perceived as an uncontrollable and difficult to manage disease. The perception of the patient is that his/her condition is not well understood and that is suffering from a disorder with hidden causes that doctors are not able to tackle. Sometimes patients go through a number of clinicians until they found some CSU expert who is familiar with the disease. It is surprising that myths and believes with no scientific support still persist. Guidelines are not widely implemented, and recent tools to assess severity are infrequently used. European and American recent guidelines do not agree in several key points related to diagnosis and treatment, which further contributes to confusion. With the aim to clarify some aspects of the CSU picture, a group of allergists and dermatologists from the Spanish Dermatology and Allergy societies developed a Frequent Asked Questions leaflet that could facilitate physicians work in daily practice and contribute to a better knowledge of common clinical scenarios related to patients with CSU.

Insights and advances in chronic urticaria: a Canadian perspective

In the past few years there have been significant advances which have changed the face of chronic urticaria. In this review, we aim to update physicians about clinically relevant advances in the classification, diagnosis and management of chronic urticaria that have occurred in recent years. These include clarification of the terminology used to describe and classify urticaria. We also detail the development and validation of instruments to assess urticaria and understand the impairment on quality-of-life and the morbidity caused by this disease. Additionally, the approach to management of chronic urticaria now focuses on evidence-based use of non-impairing, non-sedating H1-antihistamines given initially in standard doses and if this is not effective, in up to 4-fold doses. For urticaria refractory to H1-antihistamines, omalizumab treatment has emerged as an effective, safe option.

The minimal clinically important difference of the Control of Allergic Rhinitis and Asthma Test (CARAT): cross-cultural validation and relation with pollen counts

BACKGROUND

The Control of Allergic Rhinitis and Asthma Test (CARAT) monitors control of asthma and allergic rhinitis.

AIMS

To determine the CARAT's minimal clinically important difference (MCID) and to evaluate the psychometric properties of the Dutch CARAT.

METHODS

CARAT was applied in three measurements at 1-month intervals. Patients diagnosed with asthma and/or rhinitis were approached. MCID was evaluated using Global Rating of Change (GRC) and standard error of measurement (s.e.m.). Cronbach's alpha was used to evaluate internal consistency. Spearman's correlation coefficients were calculated between CARAT, the Asthma Control Questionnaire (ACQ5) and the Visual Analog Scale (VAS) on airway symptoms to determine construct and longitudinal validity. Test-retest reliability was evaluated with intra-class correlation coefficient (ICC). Changes in pollen counts were compared with delta CARAT and ACQ5 scores.

RESULTS

A total of 92 patients were included. The MCID of the CARAT was 3.50 based on GRC scores; the s.e.m. was 2.83. Cronbach's alpha was 0.82. Correlation coefficients between CARAT and ACQ5 and VAS questions ranged from 0.64 to 0.76 (P < 0.01). Longitudinally, correlation coefficients between delta CARAT scores and delta ACQ5 and VAS scores ranged from 0.41 to 0.67 (P < 0.01). Test-retest reliability showed an ICC of 0.81 (P < 0.01) and 0.80 (P < 0.01). Correlations with pollen counts were higher for CARAT than for ACQ5.

CONCLUSIONS

This is the first investigation of the MCID of the CARAT. The CARAT uses a whole-point scale, which suggests that the MCID is 4 points. The CARAT is a valid and reliable tool that is also applicable in the Dutch population.

Update on rupatadine in the management of allergic disorders

In a review of rupatadine published in 2008, the primary focus was on its role as an antihistamine, with a thorough evaluation of its pharmacology and interaction with histamine H1 -receptors. At the time, however, evidence was already emerging of a broader mechanism of action for rupatadine involving other mediators implicated in the inflammatory cascade. Over the past few years, the role of platelet-activating factor (PAF) as a potent mediator involved in the hypersensitivity-type allergic reaction has gained greater recognition. Rupatadine has dual affinity for histamine H1 -receptors and PAF receptors. In view of the Allergic Rhinitis and its Impact on Asthma group's call for oral antihistamines to exhibit additive anti-allergic/anti-inflammatory properties, further exploration of rupatadine's anti-PAF effects was a logical step forward. New studies have demonstrated that rupatadine inhibits PAF effects in nasal airways and produces a greater reduction in nasal symptoms than levocetirizine. A meta-analysis involving more than 2500 patients has consolidated the clinical evidence for rupatadine in allergic rhinoconjunctivitis in adults and children (level of evidence Ia, recommendation A). Other recent advances include observational studies of rupatadine in everyday clinical practice situations and approval of a new formulation (1 mg/ml oral solution) for use in children. In this reappraisal, we revisit some key properties and pivotal clinical studies of rupatadine and examine new clinical data in more detail including studies that measured health-related quality of life and studies that investigated the efficacy and safety of rupatadine in other indications such as acquired cold urticaria, mosquito bite allergy and mastocytosis.

Cetirizine derived supramolecular topical gel in action: rational design, characterization and in vivo self-delivery application in treating skin allergy in mice

The easiest reaction like salt formation has been exploited to design the first anti-allergic supramolecular topical gel capable of treating dinitrochlorobenzene (DNCB)-induced skin allergy in mice in a self-delivery fashion.

Brain histamine H1 receptor occupancy measured by PET after oral administration of levocetirizine, a non-sedating antihistamine

OBJECTIVE

Histamine H1 receptor (H1R) antagonists often have sedative side effects, which are caused by the blockade of the neural transmission of the histaminergic neurons. We examined the brain H1R occupancy (H1RO) and the subjective sleepiness of levocetirizine, a new second-generation antihistamine, comparing fexofenadine, another non-sedating antihistamine, as a negative active control.

METHODS

Eight healthy volunteers underwent positron emission tomography (PET) imaging with [(11)C]doxepin, a PET tracer that specifically binds to H1Rs, after a single oral administration of levocetirizine (5 mg), fexofenadine (60 mg) or placebo in a double-blind crossover study. Binding potential ratios and H1ROs in the cerebral cortices regions were calculated using placebo. Subjective sleepiness was assessed with the Line Analogue Rating Scale and the Stanford Sleepiness Scale.

RESULTS

There was no significant difference between the mean brain H1RO after levocetirizine administration (8.1%; 95% CI: -9.8 to 26.0%) and fexofenadine administration (-8.0%; 95% CI: -26.7 to 10.6%). Similarly, subjective sleepiness was not significantly different between the two antihistamines and placebo. Neither subjective sleepiness nor plasma concentrations was significantly correlated with the brain H1RO of the two antihistamines.

CONCLUSION

At therapeutic dose, levocetirizine does not bind significantly to the brain H1Rs and does not induce significant sedation.

Pediatric allergic rhinitis

Allergic rhinitis is a common pediatric problem with significant comorbidities and potential complications. This article is an overview of the epidemiology, pathophysiology, and current therapeutic strategies. Allergic rhinitis management in a specific child is age dependent and influenced by the severity and frequency of the symptoms and the presence of any concurrent conditions. Current strategies permit symptomatic control and improved quality of life for most patients.

Update and insights into treatment options for chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) is defined as itchy weals, angio-oedema, or both, arising spontaneously without external physical stimuli. Symptoms of the disease continue to develop for more than 6 weeks. It carries a high socioeconomic burden with considerable health care costs. Second generation H1-antihistamines are the mainstay of urticaria treatment and are the only licensed option. However, many patients are resistant to H1-antihistamine therapy. Omalizumab has proven to be an effective therapeutic option in patients with recalcitrant chronic urticaria. Ciclosporin appears to be more beneficial in patients with functional histamine releasing autoantibodies as a cause of their disease. This review article will highlight the major therapeutic options available today for the management of CSU knowing that good quality evidence for efficacy of many agents is scarce except for H1-antihistamines and omalizumab.

Economic burden of inadequate management of allergic diseases in the European Union: a GA(2) LEN review

BACKGROUND

In the European Union (EU), between 44 and 76 million individuals of the 217 million EU employees suffer from allergic disease of the airways or the skin. Up to 90% of these persons are untreated or insufficiently treated. This has major socio-economic consequences such as absence from work (absenteeism), particularly reduced productivity at work (presenteeism).

METHODS

We used published literature and online statistical information from Eurostat and Eurofound to assess the costs of allergic disease to society.

RESULTS

Allergies have an impact on direct, indirect, intangible and opportunity costs. Most importantly, for the EU, avoidable indirect costs per patient insufficiently treated for allergy range between €55 and €151 billion per annum due to absenteeism and presenteeism, that is, €2405 per untreated patient per year. On the other hand, appropriate therapy for allergic diseases is available at comparatively low costs at an average of €125 per patient annually, equalling only 5% of the costs of untreated disease, allowing potential savings of up to €142 billion.

CONCLUSIONS

A better care for allergies based on guideline-based treatment would allow Europe's economy substantial savings. In addition, allergies have an impact on learning and performance at school and university, leading to opportunity costs for society. This cannot be calculated moneywise but will have an impact in a modern knowledge-based society. Still allergies are trivialized in society, noting that the costs of therapy are paid by patients and healthcare services, whereas economic savings are made by employers and society. A change of this mindset is urgently needed.

Assessment of the effects of antihistamine drugs on mood, sleep quality, sleepiness, and dream anxiety

OBJECTIVE

There are limited comparative studies on classic and new-generation antihistamines that affect sleep quality and mood. The purpose of this study was to determine and compare the effects of classic and new-generation antihistamines on sleep quality, daytime sleepiness, dream anxiety, and mood.

METHODS

Ninety-two patients with chronic pruritus completed study in the dermatology outpatient clinic. Treatments with regular recommended therapeutic doses were administered. The effects of antihistaminic drugs on mood, daytime sleepiness, dream anxiety, and sleep quality were assessed on the first day and 1 month after.

RESULTS

Outpatients who received cetirizine and hydroxyzine treatments reported higher scores on the depression, anxiety, and fatigue sub-scales than those who received desloratadine, levocetirizine, and rupatadine. Pheniramine and rupatadine were found to be associated with daytime sleepiness and better sleep quality. UKU side effects scale scores were significantly elevated among outpatients receiving pheniramine. Classic antihistamines increased daytime sleepiness and decreased the sleep quality scores. New-generation antihistamines reduced sleep latency and dream anxiety, and increased daytime sleepiness and sleep quality.

CONCLUSION

Both antihistamines, significantly increased daytime sleepiness and nocturnal sleep quality. Daytime sleepiness was significantly predicted by rupadatine and pheniramine treatment. Cetirizine and hydroxyzine, seem to have negative influences on mood states. Given the extensive use of antihistamines in clinical settings, these results should be more elaborately examined in further studies.

Methods report on the development of the 2013 revision and update of the EAACI/GA2 LEN/EDF/WAO guideline for the definition, classification, diagnosis, and management of urticaria

This methods report describes the process of guideline development in detail. It is the result of a systematic literature review using the 'Grading of Recommendations Assessment, Development and Evaluation' (GRADE) methodology and a structured consensus conference held on 28 and 29 November 2012, in Berlin. It is a joint initiative of the Dermatology Section of the European Academy of Allergy and Clinical Immunology (EAACI), the EU-funded network of excellence, the Global Allergy and Asthma European Network (GA(2) LEN), the European Dermatology Forum (EDF), and the World Allergy Organization (WAO) with the participation of delegates of 21 national and international societies. This guideline covers the definition and classification of urticaria, taking into account the recent progress in identifying its causes, eliciting factors and pathomechanisms. In addition, it outlines evidence-based diagnostic and therapeutic approaches for the different subtypes of urticaria. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS) and is published in Allergy 2014; 69:868-887.

The EAACI/GA(2) LEN/EDF/WAO Guideline for the definition, classification, diagnosis, and management of urticaria: the 2013 revision and update

This guideline is the result of a systematic literature review using the 'Grading of Recommendations Assessment, Development and Evaluation' (GRADE) methodology and a structured consensus conference held on 28 and 29 November 2012, in Berlin. It is a joint initiative of the Dermatology Section of the European Academy of Allergy and Clinical Immunology (EAACI), the EU-funded network of excellence, the Global Allergy and Asthma European Network (GA(2) LEN), the European Dermatology Forum (EDF), and the World Allergy Organization (WAO) with the participation of delegates of 21 national and international societies. Urticaria is a frequent, mast cell-driven disease, presenting with wheals, angioedema, or both. The life-time prevalence for acute urticaria is approximately 20%. Chronic spontaneous urticaria and other chronic forms of urticaria do not only cause a decrease in quality of life, but also affect performance at work and school and, as such, are members of the group of severe allergic diseases. This guideline covers the definition and classification of urticaria, taking into account the recent progress in identifying its causes, eliciting factors and pathomechanisms. In addition, it outlines evidence-based diagnostic and therapeutic approaches for the different subtypes of urticaria. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS).

Night-time sedating H1 -antihistamine increases daytime somnolence but not treatment efficacy in chronic spontaneous urticaria: a randomized controlled trial

Background

Many physicians believe that the most effective way to treat chronic urticaria is to take a nonsedating second-generation H₁-antihistamine in the morning and a sedating first-generation H₁-antihistamine, usually hydroxyzine, at night to enhance sleep. But is this belief well founded?

Objectives

To test this belief by comparing the effectiveness and prevalence of unwanted sedative effects when treating patients with chronic spontaneous urticaria (CSU) with levocetirizine 15 mg daily plus hydroxyzine 50 mg at night (levocetirizine plus hydroxyzine) vs. levocetirizine 20 mg daily (levocetirizine monotherapy).

Methods

In this randomized, double-blind, cross-over study, 24 patients with difficult-to-treat CSU took levocetirizine plus hydroxyzine or levocetirizine monotherapy for periods of 5 days each. At the end of each treatment period, assessments were made of quality of life (Chronic Urticaria Quality of Life Questionnaire, CU-Q₂oL), severity of urticaria symptoms (Urticaria Activity Score, UAS), sleep disturbance during the night and daytime somnolence.

Results

Both treatments significantly decreased UAS, night-time sleep disturbances and CU-Q₂oL scores (P < 0·001) without significant differences between the two. Compared with baseline, daytime somnolence was significantly reduced by levocetirizine monotherapy (P = 0·006) but not by levocetirizine plus hydroxyzine (P = 0·218). Direct comparison of the two treatment modalities in terms of daytime somnolence favoured levocetirizine monotherapy (P = 0·026).

Conclusions

The widespread belief that sleep is aided by the addition of a sedating first-generation H₁-antihistamine, usually hydroxyzine, at night is not supported. These results are in line with the urticaria guidelines, which state that first-line treatment for urticaria should be new-generation, nonsedating H₁-antihistamines only.

Patient presentation and physician management of upper respiratory tract infections: a retrospective review of over 5 million primary clinic consultations in Hong Kong

BACKGROUND

Upper respiratory tract infection (URTI) has a significant healthcare burden worldwide. Considerable resources are consumed through health care consultations and prescribed treatment, despite evidence for little or no effect on recovery. Patterns of consultations and care including use of symptomatic medications and antibiotics for upper respiratory tract infections are poorly described.

METHODS

We performed a retrospective review of computerized clinical data on patients presenting to all public primary care clinics in Hong Kong with symptoms of respiratory tract infections. International Classification of Primary care (ICPC)codes used to identify patients included otitis media (H71), streptococcal pharyngitis (R72), acute URTI (R74), acute sinusitis (R75), acute tonsillitis (R76), acute laryngitis (R77), and influenza (R80). Sociodemographic variables such as gender, age, chronic illness status, attendance date, type and duration of drug prescribed were also collected.

RESULTS

Of the 5,529,755 primary care consultations for respiratory symptoms from 2005 to 2010, 98% resulted in a prescription. Prescription patterns of symptomatic medication were largely similar across the 5 years. In 2010 the mean number of drugs prescribed per consultation was 3.2, of which the commonly prescribed medication were sedating antihistamines (79.9%), analgesia (58.9%), throat lozenges (40.4%) and expectorant cough syrup (33.8%). During the study period, there was an overall decline in antibiotic prescription (8.1% to 5.1%). However, in consultations where the given diagnosis was otitis media (H71), streptococcal pharyngitis (R72), acute sinusitis (R75) or acute laryngitis (R76), over 90% resulted in antibiotic prescription.

CONCLUSION

There was a decline in overall antibiotic prescription over the study period. However, the use of antibiotics was high in some conditions e.g. otitis media and acute laryngitis a. Multiple symptomatic medications were given for upper respiratory tract infections. Further research is needed to develop clinical and patients directed interventions to reduce the number of prescriptions of symptomatic medications and antibiotics that could reduce costs for health care services and iatrogenic risk to patients.

Therapy of chronic urticaria: a simple, modern approach

OBJECTIVE

To examine the available treatment choices for chronic spontaneous urticaria (CSU) and discuss a new paradigm for treating such patients.

DATA SOURCES

The literature regarding treatment is reviewed, including considerations of published guidelines. Attention is focused on the most recent evidence indicating particular efficacy of omalizumab.

RESULTS

Omalizumab has been found to have considerable efficacy in phase 2 and phase 3 trials in which more than 900 patients have been studied. A response rate of 65% is seen in patients resistant to antihistamines as well as to histamine2 blockers and leukotriene antagonists, and 40% of patients are completely free of hives as long as therapy is continued. In addition, serious adverse events have not been seen. Only cyclosporine can match this response rate (excluding steroids), but the adverse effect profile (blood pressure and renal function) is substantial by comparison. Double-blind, placebo-controlled studies of other agents often listed as alternatives are lacking (ie, whether their success rate exceeds the 25%-30% placebo response is uncertain). The mechanism by which omalizumab works in CSU is not clear because the response rate is unrelated to the autoimmune profile and can occur rapidly (ie, within a few days).

CONCLUSION

Omalizumab has exceptional efficacy for antihistamine-resistant CSU with an excellent adverse effect profile.

Respiratory allergies: a general overview of remedies, delivery systems, and the need to progress

The spread of respiratory allergies is increasing in parallel with the alarm of the scientific community. Evidently, our knowledge of the onset mechanisms of these diseases and, as a consequence, of the available remedies is inadequate. This review provides a brief, general description of current therapeutic resources and the state of research with regard to both drugs and medical devices in order to highlight their limits and the urgent need for progress. Increasing the amount of basic biochemical research will improve our knowledge of such onset mechanisms and the potential efficacy of therapeutic preparations.

Prescription medication sharing: a systematic review of the literature

We reviewed the literature on nonrecreational prescription medication sharing. We searched PubMed, EMBASE, PsycINFO, and a customized multidatabase for all relevant articles published through 2013; our final sample comprised 19 studies from 9 countries with 36 182 participants, ranging in age from children to older adults, and published between 1990 and 2011. The prevalence rate for borrowing someone's prescription medication was 5% to 51.9% and for lending prescription medication to someone else was 6% to 22.9%. A wide range of medicines were shared between family members, friends, and acquaintances. Sharing of many classes of prescription medication was common. Further research should explore why people share, how they decide to lend or borrow, whether they are aware of the risks, and how they assess the relevance of those risks.

Post-mortem evidence of doxylamine in toxicological analyses

BACKGROUND

Doxylamine (DA) is widely available in pharmacies without prescription and can be used in suicidal intention because of its sedative and anticholinergic properties. Research of literature shows that only a few publications deal with post-mortem evidence of DA and its interpretation during toxicological examination.

MATERIAL AND METHODS

In this study, all cases with a positive detection of DA during toxicological analyses with high-performance liquid chromatography in the time period 2000 to 2010 at the Institute of Legal Medicine and Forensic Sciences in Berlin, Germany were retrospectively analysed and interpreted, taking into account police investigations, autopsy results and toxicological analyses.

RESULTS

In total, 22 cases with DA intoxications were discovered (♂=16/♀=6, age-at-death range 17 to 90years). Maximum blood concentration was measured at 77.5μg/mL. Cause of death was due to DA intoxication in eight suicide cases; seven of those were combined intoxications (DA and other substances, particularly diphenhydramine). During the evaluated time period no monointoxications with DA were discovered.

CONCLUSION

Benchmarks published in past literature are meant as orientation during evaluation of post-mortem DA evidence. These should not be used as absolute values and need to be interpreted individually in each case. Post-mortem redistribution needs to be considered as a main factor in alteration of DA concentration measurement. Furthermore, proof of DA ingestion found in gastric content should only be interpreted quantitatively due to unreliable calculation of the ingested amount. In conclusion, a variety of factors, such as the time period between time of death and the time of the first toxicological analysis, the condition of the body and the findings at autopsy, must also be critically considered.

Paediatric rhinitis: position paper of the European Academy of Allergy and Clinical Immunology

Rhinitis is a common problem in childhood and adolescence and impacts negatively on physical, social and psychological well-being. This position paper, prepared by the European Academy of Allergy and Clinical Immunology Taskforce on Rhinitis in Children, aims to provide evidence-based recommendations for the diagnosis and therapy of paediatric rhinitis. Rhinitis is characterized by at least two nasal symptoms: rhinorrhoea, blockage, sneezing or itching. It is classified as allergic rhinitis, infectious rhinitis and nonallergic, noninfectious rhinitis. Similar symptoms may occur with other conditions such as adenoidal hypertrophy, septal deviation and nasal polyps. Examination by anterior rhinoscopy and allergy tests may help to substantiate a diagnosis of allergic rhinitis. Avoidance of relevant allergens may be helpful for allergic rhinitis (AR). Oral and intranasal antihistamines and nasal corticosteroids are both appropriate for first-line AR treatment although the latter are more effective. Once-daily forms of corticosteroids are preferred given their improved safety profile. Potentially useful add-on therapies for AR include oral leukotriene receptor antagonists, short bursts of a nasal decongestant, saline douches and nasal anticholinergics. Allergen-specific immunotherapy is helpful in IgE-mediated AR and may prevent the progression of allergic disease. There are still a number of areas that need to be clarified in the management of rhinitis in children and adolescents.

The effect of a first-generation H1-antihistamine on postural control: a preliminary study in healthy volunteers

First-generation H1-antihistamines are known to cause fatigue and drowsiness, due to their poor receptor selectivity and their high penetration rate of the blood-brain barrier. However, little is known about the effects of first-generation H1-antihistamines on postural stability. The purpose of this study was to evaluate the effects of d-chlorpheniramine on postural stability using posturography with and without foam rubber. A double-blind study with three parallel groups was conducted. Twenty-seven healthy young volunteers (mean age 21.9 years) were recruited and orally administered d-chlorpheniramine, 2 or 4 mg, or placebo. Postural sway was measured every hour up to 8 h after administration. Two-legged stance tasks were performed by each subject in four conditions: eyes open or eyes closed and with or without foam rubber. Inter-group comparisons showed that the group receiving 4-mg d-chlorpheniramine showed significantly larger sway in the eyes open with foam rubber condition (visual and vestibular information available, somatosensory information reduced). Inter-subject analysis in the 4-mg d-chlorpheniramine group showed that the effect of d-chlorpheniramine on postural control was variable. Our results suggest that among the three main sensory systems responsible for postural control (visual, vestibular, and somatosensory), d-chlorpheniramine may have a larger effect on the visual and/or vestibular systems in susceptible individuals.

Disease activity only moderately correlates with quality of life impairment in patients with chronic spontaneous urticaria

BACKGROUND

The impact of chronic spontaneous urticaria (CSU) on health-related quality of life (HRQoL) is widely held to be mainly influenced by disease activity and comorbidities.

OBJECTIVE

To assess the correlation between disease activity and HRQoL impairment by using validated disease-specific instruments.

METHODS

The Chronic Urticaria Quality of Life Questionnaire (CU-Q2oL) was translated into Greek and subsequently applied to 110 CSU patients along with the Dermatology Life Quality Index and the Urticaria Activity Score. After the validity and reliability of the Greek CU-Q2oL had been determined, we assessed the relation between disease activity and HRQoL impairment by computing correlations as well as by performing multiple regression analysis.

RESULTS

Exploratory factor analysis revealed a six-scale structure of the Greek CU-Q2oL that explained 67.9% of its total variance. The internal consistency was satisfactory with Cronbach's α >0.7. Disease activity was the only predictor of quality of life impairment, but it only moderately correlated with the CU-Q2oL total score (r = 0.40, p < 0.0001).

CONCLUSION

Our results suggest that there are additional factors to disease activity that are responsible for the pronounced reduction of HRQoL in CSU, and this supports the recommendation to assess and monitor both disease activity and quality of life in CSU patients.

The clinical use of cetirizine in the treatment of allergic rhinitis

BACKGROUND

Cetirizine is among the first second-generation H1 antihistamines (SGAHs) developed to provide selective H1 receptor inhibition without central nervous system depression.

OBJECTIVE

The aim of this review is to summarize the amount of data collected over 25 years of clinical use of cetirizine and compare this with data available for other SGAHs in the management of patients with allergic rhinitis (AR).

METHODS

A comprehensive literature search for publications relating to cetirizine was performed using the Pubmed database, and relevant papers published in English were selected for detailed review.

RESULTS

Compared with the majority of other SGAHs, cetirizine was generally shown to have a more favourable pharmacological profile, to be well tolerated, be at least equally or more efficacious in attenuating/inhibiting nasal and ocular symptoms and to improve the quality of life in AR patients. The majority of clinical trials investigating the effect of SGAHs in AR patients further indicated that cetirizine was often employed as the main comparator active drug.

CONCLUSION

Based on the evidence that cetirizine is a commonly employed active comparator drug in AR, it is tempting to suggest that cetirizine may be a suitable benchmark in the development of novel pharmacotherapies for AR.

Pharmacology of antihistamines

H1-antihistamines, the mainstay of treatment for urticaria, were developed from anticholinergic drugs more than 70 years ago. They act as inverse agonists rather than antagonists of histamine H1-receptors which are members of the G-protein family. The older first generation H1-antihistamines penetrate readily into the brain to cause sedation, drowsiness, fatigue and impaired concentration and memory causing detrimental effects on learning and examination performance in children and on impairment of the ability of adults to work and drive. Their use should be discouraged. The newer second-generation H1-antihistamines are safer, cause less sedation and are more efficacious. Three drugs widely used for symptomatic relief in urticaria, desloratadine, levocetirizine and fexofenadine are highlighted in this review. Of these levocetirizine and fexofenadine are the most potent in humans in vivo. However, levocetirizine may cause somnolence in susceptible individuals, whereas fexofenadine has a relatively short duration of action and may be required to be given twice daily for all round daily protection. Although desloratadine is less potent, it has the advantages of rarely causing somnolence and having a long duration of action.

Current and future directions in pediatric allergic rhinitis

BACKGROUND

Allergic rhinitis (AR) is a common pediatric problem that significantly affects sleep, learning, performance, and quality of life. In addition, it is associated with significant comorbidities and complications.

OBJECTIVE

The aim was to provide an update on the epidemiology, comorbidities, pathophysiology, current treatment, and future direction of pediatric AR.

METHODS

Literature reviews in each of these areas were conducted, and the results were incorporated.

RESULTS

The prevalence of AR is increasing in the pediatric population and is associated with significant morbidity, comorbidities, and complications. The mainstay of current treatment strategies includes allergen avoidance, pharmacotherapy, and allergen specific immunotherapy.

CONCLUSIONS

In the future, diagnosis will be improved by microarrayed recombinant allergen testing and therapy will be expanded to include emerging treatments such as sublingual immunotherapy and combination products.

Safety evaluation of desloratadine in allergic rhinitis

INTRODUCTION

Desloratadine is a biologically active metabolite of second-generation antihistamine loratadine. It is also indicated for the treatment of allergic diseases, including allergic rhinitis.

AREAS COVERED

A Medline search was conducted to identify preclinical and clinical studies of desloratadine. This was supplemented with additional articles obtained from online sources. The focus of this review is on the safety profile of desloratadine.

EXPERT OPINION

The review of these data indicates that the safety profile of desloratadine is similar to other second-generation antihistamines. Desloratadine is highly selective for histamine H₁-receptors, does not cross the blood-brain barrier (BBB), and has minimal adverse events (very low sedation rate), with a better safety and tolerability than first-generation antihistamines. Desloratadine is safe and well tolerated without having central nervous system (CNS) or cardiovascular effects and with low drug interaction.

Impact of early diagnosis and control of chronic respiratory diseases on active and healthy ageing. A debate at the European Union Parliament

A debate at the European Union Parliament was held on 13 November 2012 on the Impact of early diagnosis and control of chronic respiratory diseases on Active and Healthy Ageing (AHA). The debate was held under the auspices of the Cyprus Presidency of the European Union (2012) and represents a follow-up of the priorities of the Polish Presidency of the European Union (2011). It highlighted the importance of early life events on the occurrence of chronic respiratory diseases later in life and their impact on active and healthy ageing. Epidemiologic evidence was followed by actions that should be taken to prevent and manage chronic respiratory diseases in children. The debate ended by practical, feasible and achievable projects, demonstrating the strength of the political action in the field. Three projects will be initiated from this debate: The first will be a meeting sponsored by the Région Languedoc-Roussillon on the developmental origins of chronic diseases and ageing: from research to policies and value creation. The second project is being led by the WHO Collaborating Centre for Asthma and Rhinitis: Prevention of Asthma, Prevention of Allergy (PAPA). The third project is the GA(2)LEN sentinel network.

Pharmacology of antihistamines

This article reviews the molecular biology of the interaction of histamine with its H1-receptor and describes the concept that H1-antihistamines are not receptor antagonists but are inverse agonists i.e. they produce the opposite effect on the receptor to histamine. It then discourages the use of first-generation H1-antihistamines in clinical practice today for two main reasons. First, they are less effective than second generation H1-antihistamines. Second, they have unwanted side effects, particularly central nervous system and anti-cholinergic effects, and have the potential for causing severe toxic reactions which are not shared by second-generation H1-antihistamines. There are many efficacious and safe second-generation H1-antihistamines on the market for the treatment of allergic disease. Of the three drugs highlighted in this review, levocetirizine and fexofenadine are the most efficacious in humans in vivo. However, levocetirizine may cause somnolence in susceptible individuals while fexofenadine has a relatively short duration of action requiring twice daily administration for full all round daily protection. While desloratadine is less efficacious, it has the advantages of rarely causing somnolence and having a long duration of action. Lastly, all H1-antihistamines have anti-inflammatory effects but it requires regular daily dosing rather than dosing 'on-demand' for this effect to be clinically demonstrable.

Pharmacology of antihistamines

This article reviews the molecular biology of the interaction of histamine with its H₁-receptor and describes the concept that H₁-antihistamines are not receptor antagonists but are inverse agonists i.e. they produce the opposite effect on the receptor to histamine. It then discourages the use of first-generation H₁-antihistamines in clinical practice today for two main reasons. First, they are less effective than second generation H₁-antihistamines. Second, they have unwanted side effects, particularly central nervous system and anti-cholinergic effects, and have the potential for causing severe toxic reactions which are not shared by second-generation H₁-antihistamines. There are many efficacious and safe second-generation H₁-antihistamines on the market for the treatment of allergic disease. Of the three drugs highlighted in this review, levocetirizine and fexofenadine are the most efficacious in humans in vivo. However, levocetirizine may cause somnolence in susceptible individuals while fexofenadine has a relatively short duration of action requiring twice daily administration for full all round daily protection. While desloratadine is less efficacious, it has the advantages of rarely causing somnolence and having a long duration of action. Lastly, all H₁-antihistamines have anti-inflammatory effects but it requires regular daily dosing rather than dosing 'on-demand' for this effect to be clinically demonstrable.

Molecular and cellular analysis of human histamine receptor subtypes

The human histamine receptors hH(1)R and hH(2)R constitute important drug targets, and hH(3)R and hH(4)R have substantial potential in this area. Considering the species-specificity of pharmacology of H(x)R orthologs, it is important to analyze hH(x)Rs. Here, we summarize current knowledge of hH(x)Rs endogenously expressed in human cells and hH(x)Rs recombinantly expressed in mammalian and insect cells. We present the advantages and disadvantages of the various systems. We also discuss problems associated with the use of hH(x)R antibodies, an issue of general relevance for G-protein-coupled receptors (GPCRs). There is much greater overlap in activity of 'selective' ligands for other hH(x)Rs than the cognate receptor subtype than generally appreciated. Studies with native and recombinant systems support the concept of ligand-specific receptor conformations, encompassing agonists and antagonists. It is emerging that for characterization of hH(x)R ligands, one cannot rely on a single test system and a single parameter. Rather, multiple systems and parameters have to be studied. Although such studies are time-consuming and expensive, ultimately, they will increase drug safety and efficacy.

Update in clinical allergy and immunology

In the recent years, a tremendous body of studies has addressed a broad variety of distinct topics in clinical allergy and immunology. In this update, we discuss selected recent data that provide clinically and pathogenetically relevant insights or identify potential novel targets and strategies for therapy. The role of the microbiome in shaping allergic immune responses and molecular, as well as cellular mechanisms of disease, is discussed separately and in the context of atopic dermatitis, as an allergic model disease. Besides summarizing novel evidence, this update highlights current areas of uncertainties and debates that, as we hope, shall stimulate scientific discussions and research activities in the field.

Toxicological identification of diphenhydramine (DPH) in suicide

Diphenhydramine (DPH), an H1-antihistamine, is identified during postmortem toxicological analyses on a relatively rare but still regular basis. This study examines suicidal intoxications with DPH by analyzing blood and gastric content concentration levels. Twenty cases of DPH intoxications within a 10-year period (2000-2010) were discovered by screening the autopsy records of the Institute of Legal Medicine and Forensic Sciences (ILMFS) in Berlin, Germany. In four cases, DPH levels were lower than 1 μg/mL and hence were not considered likely to be responsible for causing death. In 11 cases, DPH played a role in the fatal episode, and five of these cases were monointoxications. Considering that more than 8,000 autopsies were performed by the ILMFS within the time period under examination, there is only one monointoxication case every 2 years, which makes it a rare occurrence. In two of these intoxications, DPH was only measured in toxic but not "lethal" concentrations in blood, with a concentration of 5 μg/mL being generally used as the cut off between categories according to forensic literature. This raises the question as to whether a strict boundary for a "lethal" blood concentration, as suggested in some literature, can be set and applied in any of these cases. This study shows that an individual interpretation of each case is of utmost importance for correct classification. A thorough toxicological analysis of peripheral venous blood and gastric content, as well as a detailed work-up of the death circumstances, are the basis of an exact interpretation of intoxications with DPH.

Severe chronic allergic (and related) diseases: a uniform approach--a MeDALL--GA2LEN--ARIA position paper

Concepts of disease severity, activity, control and responsiveness to treatment are linked but different. Severity refers to the loss of function of the organs induced by the disease process or to the occurrence of severe acute exacerbations. Severity may vary over time and needs regular follow-up. Control is the degree to which therapy goals are currently met. These concepts have evolved over time for asthma in guidelines, task forces or consensus meetings. The aim of this paper is to generalize the approach of the uniform definition of severe asthma presented to WHO for chronic allergic and associated diseases (rhinitis, chronic rhinosinusitis, chronic urticaria and atopic dermatitis) in order to have a uniform definition of severity, control and risk, usable in most situations. It is based on the appropriate diagnosis, availability and accessibility of treatments, treatment responsiveness and associated factors such as comorbidities and risk factors. This uniform definition will allow a better definition of the phenotypes of severe allergic (and related) diseases for clinical practice, research (including epidemiology), public health purposes, education and the discovery of novel therapies.