Prevention of acute urticaria in young children with atopic dermatitis

Cetirizine use in childhood: an update of a friendly 30-year drug

Cetirizine is a second-generation antihistamine, derived from the metabolism of hydroxyzine, highly specific for the H1 receptors, and with marked antiallergic properties. Although its history began more than 30 years ago, it remains one of the most used drugs in children with a leading role in the medical care of children with allergic diseases. Cetirizine use is licensed for paediatric patients for the treatment of allergic rhinitis, and chronic spontaneous urticaria, in Europe in children older than 2 years old and in the USA in children older than 6 months old. This review provides a practical update on the use of cetirizine in children and adolescents.

Management of Pediatric Urticaria with Review of the Literature on Chronic Spontaneous Urticaria in Children

There are substantial knowledge gaps related to diagnosis and management of pediatric cases of chronic urticaria, and in particular chronic spontaneous urticaria (CSU). In this article we aimed to review the diagnosis and management of chronic urticaria in children and CSU in particular. We conducted a systematic review of articles published in English and French on pediatric CSU management in the last 10 years. We included experimental studies (eg, randomized controlled trials), other experimental designs (eg, nonrandomized methods of assignment, controlled before-after studies, and interrupted time series), and observational studies (eg, prospective or retrospective cohort studies, cross-sectional studies, case-control studies, and case reports). Our findings highlight the efficacy of second-generation antihistamines for the treatment of CSU in children and supports the use of omalizumab for more severe cases. However, our study also reveals severe knowledge gaps related to the best management strategy in children with more severe/refractory cases of CSU. Future studies are required to establish the beneficial effect of high doses of second-generation antihistamines as well as the effectiveness and safety of omalizumab and other biologics in young children.

A Comprehensive Review of the Treatment of Atopic Eczema

Atopic eczema (AE) is a chronic, inflammatory skin disorder which usually develops in early childhood. In spite of intensive investigations, the causes of AE remain unclear, but are likely to be multifactorial in nature. Environmental factors or genetic-environmental interactions seem to play a key role in disease progression. Among various measures of AE managment, cutaneous hydration, which improves barrier function and relieve itchiness, may be helpful to reduce the need for topical steroid use and therefore should be used as a basic treatment. Avoiding aggravating factors is also a basic treatment of AE. Standard medical treatment with a pharmacologic approach may be necessary if basic treatment fails to control symptoms satisfactorily. Recently, more attention is given to a proactive therapeutic by regular intermittent application of low potency steroids or topical calcineurin inhibitors to prevent new flares. Furthermore, various targeted biologics are being introduced for AE control and are proposed as promising therapies. This paper provides a summary of the recent literature on the manangement of AE and a treatment guideline.

Demographic and clinical profiles in patients with acute urticaria

BACKGROUND

Urticaria is a common cause for consultation in general and specialised medical practices. There is scarce information on the characteristics of patients suffering acute urticaria in Latin America.

OBJECTIVES

To investigate demographic and clinical features of patients with acute urticaria attending two allergy clinics in Caracas, Venezuela.

METHODS

A prospective study of all new patients who consulted during a three-year period because of acute urticaria. Information on age, gender, symptom duration, previous medical history, body distribution of wheals and angio-oedema, laboratory investigations, skin prick tests, and pharmacological treatment, was collected. Patients were classified according to their age as children/adolescents and adults.

RESULTS

Two hundred and forty eight patients (177 adults and 71 children) were studied. Acute urticaria was more frequent in middle-aged atopic female patients. Lesions more often involved upper and lower limbs and head, and 31% of patients exhibited generalised urticaria. Laboratory investigations, performed only in selected cases, did not contribute to the final diagnosis. Most frequent subtypes of acute urticaria were spontaneous, dermographic, papular, and drug-induced urticaria. Most patients were treated with non-sedating antihistamines, with increased use of cetirizine and levocetirizine in children, while 5.6% of children and 20.3% of adults required the addition of short courses of systemic corticosteroids.

CONCLUSIONS

Acute urticaria is a frequent cause of consultation for allergists, affecting more often middle-aged female atopic patients. The use of extensive complementary tests does not seem to be cost-effective for this clinical condition. Spontaneous, dermographic, papular and drug-induced urticaria are the most common subtypes.

Chronic pruritus associated with dermatologic disease in infancy and childhood: update from an interdisciplinary group of dermatologists and pediatricians

An effective treatment strategy for chronic pruritus in children with dermatologic disorders should consider the multidimensional aspects of pruritus, the unique challenges associated with treating pruritic skin disorders in the pediatric population, and evidence-based therapies with demonstrated antipruritic benefits and clinically relevant effects on patient/family quality of life (QoL). The Course of Advanced Learning for the Management of ITch (CALM-IT) Task Force is an interdisciplinary group of experts specializing in core aspects of pruritus treatment, integrating pediatrics, dermatology, psychotherapy, pruritus management, and sleep. CALM-IT recently convened to provide updated guidance on managing chronic pruritus associated with dermatologic diseases in pediatric patients, with a special focus on atopic dermatitis (AD) and chronic spontaneous urticaria (csU). This review highlights the updated concepts and best practices, which were built upon international PRACTALL consensus and modified for children and infants with AD and csU. CALM-IT supports the routine use of basic skin therapy and the escalation of topical medications, according to severity and focused on rapid itch control. Anti-inflammatory agents should be appropriate for infants and children (i.e., with an optimized therapeutic index) and have proven antipruritic properties, such as those demonstrated by methylprednisolone aceponate. New experimental findings do not support the use of non-sedating oral antihistamines as adjuvant antipruritic therapy for AD. In csU, oral H1 -antihistamine use is justified, consistent with the distinct pathophysiologic mechanisms of itch underlying AD and csU. All encompassing QoL assessments should consider the burden of both patient and caregiver and should address outstanding unmet clinical needs of pediatric patients. Future research areas include integrated QoL assessments and multidisciplinary treatment programs with pediatric-targeted pruritic therapies providing rapid itch control.

Atopic dermatitis: a practice parameter update 2012

This parameter was developed by the Joint Task Force on Practice Parameters, representing the American Academy of Allergy, Asthma & Immunology (AAAAI); the American College of Allergy, Asthma & Immunology (ACAAI); and the Joint Council of Allergy, Asthma and Immunology. The AAAAI and the ACAAI have jointly accepted responsibility for establishing "Atopic dermatitis: a practice parameter update 2012." This is a complete and comprehensive document at the current time. The medical environment is a changing environment, and not all recommendations will be appropriate for all patients. Because this document incorporated the efforts of many participants, no single individual, including those who served on the Joint Task Force, is authorized to provide an official AAAAI or ACAAI interpretation of these practice parameters. Any request for information about or an interpretation of these practice parameters by the AAAAI or ACAAI should be directed to the Executive Offices of the AAAAI, the ACAAI, and the Joint Council of Allergy, Asthma & Immunology. These parameters are not designed for use by pharmaceutical companies in drug promotion. Published practice parameters of the Joint Task Force on Practice Parameters for Allergy & Immunology are available online at http://www.jcaai.org.

Diagnosis and treatment of urticaria and angioedema: a worldwide perspective

: Urticaria and angioedema are common clinical conditions representing a major concern for physicians and patients alike. The World Allergy Organization (WAO), recognizing the importance of these diseases, has contributed to previous guidelines for the diagnosis and management of urticaria. The Scientific and Clinical Issues Council of WAO proposed the development of this global Position Paper to further enhance the clinical management of these disorders through the participation of renowned experts from all WAO regions of the world. Sections on definition and classification, prevalence, etiology and pathogenesis, diagnosis, treatment, and prognosis are based on the best scientific evidence presently available. Additional sections devoted to urticaria and angioedema in children and pregnant women, quality of life and patient-reported outcomes, and physical urticarias have been incorporated into this document. It is expected that this article will supplement recent international guidelines with the contribution of an expert panel designated by the WAO, increasing awareness of the importance of urticaria and angioedema in medical practice and will become a useful source of information for optimum patient management worldwide.

Chronic spontaneous urticaria in children: itching for insight

While there is increasing information about the pathogenesis and treatment of chronic spontaneous urticaria (csU) in adults, there is little published information about csU in children. Consequently, most of the recommendations contained in current guidelines for the prevention and treatment of csU in infants and children is based on extrapolation of data obtained in adults. To rectify this, this review points out critical gaps in our knowledge and suggests strategies which may help us to improve our understanding of this condition. How common is csU in children? What do we know about its clinical presentation and the presence of useful biomarkers? What are its common underlying causes? What is the course of csU in children? How does csU affect the everyday life of children? What treatment options are available for children? To answer these questions, two separate types of information are required. The first is information about the prevalence of the condition in the community at large and how csU affects the everyday life of both the child-patient and the parent or carer. Because most csU cases in infants and children do not come to specialists but are treated by general practitioners or by parents using over-the-counter medications, these questions may be answered only by general population surveys or schools programmes. The second is clinical information including family history and disease presentation, the presence of biomarkers and comorbidities, objective measures of severity, frequency and duration of exacerbations, the response to therapy and the time to remission. Targeted questionnaires need to be developed and validated for these investigations. This has already begun in Germany with the establishment of the CU-KID Netzwerk (Email address: cu-kid@charite.de), the aim of which is to identify clinical centres and colleagues who treat children with urticaria and to initiate the information gathering described above.

EAACI/GA(2)LEN/EDF/WAO guideline: management of urticaria

This guideline, together with its sister guideline on the classification of urticaria (Zuberbier T, Asero R, Bindslev-Jensen C, Canonica GW, Church MK, Giménez-Arnau AM et al. EAACI/GA(2)LEN/EDF/WAO Guideline: definition, classification and diagnosis of urticaria. Allergy 2009;64: 1417-1426), is the result of a consensus reached during a panel discussion at the Third International Consensus Meeting on Urticaria, Urticaria 2008, a joint initiative of the Dermatology Section of the European Academy of Allergology 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). As members of the panel, the authors had prepared their suggestions regarding management of urticaria before the meeting. The draft of the guideline took into account all available evidence in the literature (including Medline and Embase searches and hand searches of abstracts at international allergy congresses in 2004-2008) and was based on the existing consensus reports of the first and the second symposia in 2000 and 2004. These suggestions were then discussed in detail among the panel members and with the over 200 international specialists of the meeting to achieve a consensus using a simple voting system where appropriate. Urticaria has a profound impact on the quality of life and effective treatment is, therefore, required. The recommended first line treatment is new generation, nonsedating H(1)-antihistamines. If standard dosing is not effective, increasing the dosage up to four-fold is recommended. For patients who do not respond to a four-fold increase in dosage of nonsedating H(1)-antihistamines, it is recommended that second-line therapies should be added to the antihistamine treatment. In the choice of second-line treatment, both their costs and risk/benefit profiles are most important to consider. Corticosteroids are not recommended for long-term treatment due to their unavoidable severe adverse effects. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS).

New oral H1 antihistamines in children: facts and unmeet needs

BACKGROUND

Second-generation antihistamines differ from first-generation ones because of their elevated specificity and affinity for peripheral H1-receptors and because of their lower penetration to the central nervous system, having fewer sedative effects as a result. Over the last few years, new compounds with different pharmacokinetic properties have been synthesized. More recent improvements of the molecules, generally in the form of active metabolites, led to the synthesis of new-generation antihistamines.

METHODS

Recommendations on the minimum criteria that would have to be met for compounds to be classified as new-generation antihistamines have been recently established by a consensus statement. In the past, the pharmacokinetics and pharmacodynamics of H1 antihistamines have not been optimally investigated in the pediatric population, especially in infants and young children.

RESULTS

The pharmacology of second-generation H1 antihistamines has been investigated relatively deeper than old antihistamines in children. In the pediatric population, clinical studies with new-generation antihistamines are still limited in number and, with rare exceptions, of brief duration. Comparative trials on the efficacy and safety between different compounds are also lacking.

CONCLUSIONS

Properly designed, long-term trials with new-generation H1 antihistamines need to be performed in single age groups, in order to better define the effects of these drugs in all pediatric population.

H1 antihistamines: current status and future directions

In this review, we compare and contrast the clinical pharmacology, efficacy, and safety of first-generation H1 antihistamines and second-generation H1 antihistamines. First-generation H1 antihistamines cross the blood-brain barrier, and in usual doses, they potentially cause sedation and impair cognitive function and psychomotor performance. These medications, some of which have been in use for more than 6 decades, have never been optimally investigated. Second-generation H1 antihistamines such as cetirizine, desloratadine, fexofenadine, levocetirizine, and loratadine cross the blood-brain barrier to a significantly smaller extent than their predecessors. The clinical pharmacology, efficacy, and safety of these medications have been extensively studied. They are therefore the H1 antihistamines of choice in the treatment of allergic rhinitis, allergic conjunctivitis, and urticaria. In the future, clinically advantageous H1 antihistamines developed with the aid of molecular techniques might be available.

Cetirizine in horses: Pharmacokinetics and pharmacodynamics following repeated oral administration

The pharmacokinetics of the histamine H(1)-antagonist cetirizine and its effect on histamine-induced cutaneous wheal formation were studied in six healthy horses following repeated oral administration. After three consecutive administrations of cetirizine (0.2 mg/kg body weight, bw) every 12h, the trough plasma concentration of cetirizine was 16+/-4 ng/mL (mean+/-SD) and the wheal formation was inhibited by 45+/-23%. After four additional administrations of cetirizine (0.4 mg/kg bw) every 12 h, the trough plasma concentration was 48+/-15 ng/mL and the wheal formation was inhibited by 68+/-11%. The terminal half-life was about 5.8 h. A pharmacokinetic/pharmacodynamic link model showed that the maximal inhibition of wheal formation was about 95% and the EC(50) about 18 ng/mL. It is concluded that cetirizine in doses of 0.2-0.4 mg/kg bw administered at 12 h intervals exhibits favourable pharmacokinetic and pharmacodynamic properties without causing visible side effects, and the drug may therefore be a useful antihistamine in equine medicine.

Other Allergic Skin Disorders

In this chapter we discuss allergic skin disorders other than atopic dermatitis (AD): the urticaria-angioedema syndrome, allergic contact dermatitis (ACD), protein contact dermatitis (PCD), phytodermatitis, allergic photodermatitis and allergic vasculitis.

H1-antihistamine treatment in young atopic children: effect on urticaria

BACKGROUND

There are few published, randomized, double-masked, placebo-controlled, clinical trials of interventions for urticaria in the pediatric population.

OBJECTIVE

To study the effect of long-term treatment with the H1-antihistamine levocetirizine on urticaria in young atopic children.

METHODS

In the randomized, double-masked, parallel-group Early Prevention of Asthma in Atopic Children Study, children with atopic dermatitis aged 12 to 24 months at enrollment received levocetirizine, 0.125 mg/kg, or matching placebo twice daily for 18 months. On a diary card, the child's caregiver recorded the days on which urticaria was observed. This was validated by the study investigator and entered into the electronic case report form, along with any additional relevant information.

RESULTS

A total of 510 atopic children (mean +/- SEM age, 19.4 +/- 0.2 months) composed the intention-to-treat population. During the subsequent 18 months, 27.5% (70/255) of the children taking levocetirizine and 41.6% (106/255) of the children taking placebo experienced urticaria (P < .001). The mean +/- SEM number of urticaria episodes was 0.71 +/- 0.11 in those receiving levocetirizine and 1.71 +/- 0.25 in those receiving placebo (P < .001). The mean +/- SEM duration of urticaria episodes was 4.43 +/- 1.57 days in those receiving levocetirizine and 5.36 +/- 1.27 days in those receiving placebo (P < .001).

CONCLUSIONS

Urticaria is common in atopic toddlers and deserves recognition as an important disorder that occurs early in the atopic marathon. Regular long-term treatment with levocetirizine effectively prevents and treats urticaria in young children. The results of this study strengthen the evidence base for the use of relatively nonsedating, second-generation H1-antihistamines in the pediatric population.

Cetirizine in horses: pharmacokinetics and effect of ivermectin pretreatment

The pharmacokinetics of the histamine H(1)-antagonist cetirizine and the effects of pretreatment with the antiparasitic macrocyclic lactone ivermectin on the pharmacokinetics of cetirizine were studied in horses. After oral administration of cetirizine at 0.2 mg/kg bw, the mean terminal half-life was 3.4 h (range 2.9-3.7 h) and the maximal plasma concentration 132 ng/mL (101-196 ng/mL). The time to reach maximal plasma concentration was 0.7 h (0.5-0.8 h). Ivermectin (0.2 mg/kg bw) given orally 1.5 h before cetirizine did not affect its pharmacokinetics. However, ivermectin pretreatment 12 h before cetirizine increased the area under the plasma concentration-time curve by 60%. The maximal plasma concentration, terminal half-life and mean residence time also increased significantly following the 12 h pretreatment. Ivermectin is an inhibitor of P-glycoprotein, which is a major drug efflux transporter in cellular membranes at various sites. The elevated plasma levels of cetirizine following the pretreatment with ivermectin may mainly be due to decreased renal secretion, related to inhibition of the P-glycoprotein in the proximal tubular cells of the kidney. The pharmacokinetic properties of cetirizine have characteristics which are suitable for an antihistamine, and this substance may be a useful drug in horses.

EAACI/GA2LEN/EDF guideline: management of urticaria

This guideline is the result of a consensus reached during a panel discussion at the second International Consensus Meeting on Urticara, Urticaria 2004, a joint initiative of the EAACI Dermatology Section and GA2LEN. Urticaria has a profound impact on the quality of life, and effective treatment is therefore required. The recommended first line treatment are nonsedating H1 antihistamines. They have proven to be effective in double-blind controlled studies, but dosages increased up to fourfold over the recommended doses may be necessary. However, for different urticaria subtypes and in view of individual variation in the course of the disease and response to treatment, additional or alternative therapies may be required. Immunosuppressive drugs like cyclosporin A and corticosteroids are not recommended for long-term treatment due to unavoidable severe adverse effects. This guideline was, in addition, accepted by the European Dermatology Forum (EDF) and formally approved by the European Union of Medical Specialists (UEMS).

Urticária

A urticária apresenta-se com diversas formas clínicas e causas distintas. Constitui uma das dermatoses mais freqüentes: 15% a 20% da população têm pelo menos um episódio agudo da doença em sua vida, resultando em percentual que varia de um a 2% dos atendimentos nas especialidades de Dermatologia e Alergologia. A urticária é classificada do ponto de vista de duração da evolução temporal em aguda (inferior a seis semanas) ou crônica (superior a seis semanas). O tratamento da urticária pode compreender medidas não farmacológicas e intervenções medicamentosas, as quais são agrupadas em tratamentos de primeira (anti-histamínicos), segunda (corticosteróides e antileucotrienos) e terceira linha (medicamentos imunomoduladores). As medidas terapêuticas de segunda e terceira linha apresentam maiores efeitos adversos, devendo ser reservadas aos doentes que não apresentaram controle da doença com os de primeira linha, ou àqueles a respeito dos quais não é possível estabelecer uma etiologia, tal como nas urticárias auto-imunes.

Antihistamines in Dermatology

Along with antibiotics, antihistamines are the most widely used systemic drugs in dermatology. This is attributable to the major role played by histamine in common diseases such as urticaria and atopic eczema. Of the currently recognised four subtypes of G protein-coupled histamine receptors, only the H1 and H2 subtypes have been positively identified in human skin. Traditionally believed to be competitive antagonists of histamine, H1 and H2 antihistamines are now considered to behave as inverse agonists. By consensus, H1 antihistamines are classified as 'first generation' (associated with troublesome side-effects including somnolence, anti-adrenergic and atropine-like actions) and 'second-generation' compounds (in which these side-effects are reduced or absent). The main indications for H1 antihistamines in skin are suppression of pruritus in urticaria and atopic eczema, both of which are associated with increased mast cell numbers and tissue histamine levels. However the evidence basis for use in atopic eczema is ambiguous and controversial, even though these drugs are widely used in practice. Currently, significant side-effects are mainly confined to the first-generation compounds and are especially troublesome in the elderly. Psychomotor impairment may persist throughout the day following administration. Anti-cholinergic and anti-alpha-adrenergic blockade and cardiotoxicity (torsade de pointes) may also occur with first-generation antihistamines. Two early low-sedation second-generation antihistamines caused arrhythmias in a small number of patients but these compounds have now been withdrawn. Generally, the second-generation H1 antihistamines are well tolerated.

Les anti-H1 en pratique dermatologique

INTRODUCTION

Histamine is an inflammation mediator that is fundamental for the development of some allergic reactions and is also implied in several common dermatological affections. Anti-H1s are molecules capable of couteracting the effect of histamine on its specific receptors. There are two types: first generation anti-H1 and second generation anti-H1.

OBJECTIVE

To assess the efficacy of anti-H1 in the treatment of skin diseases.

PATIENTS AND METHODS

A reference search was made using the Pubmed data bank. Critical analysis was made of the articles selected based on their evidence.

RESULTS AND CONCLUSION

Demonstration of the efficacy of anti-H1 was only confirmed in a few dermatitis. Urticaria is the indication of choice. The symptomatic use of anti-H1 may be justified within the context of other dermatitis. The second rather than the first generation molecules should be preferred because of the lesser side effects and improved pharmacokinetic profile.

Population pharmacokinetics of levocetirizine in very young children: the pediatricians' perspective

Developmental changes during infancy and childhood can affect drug pharmacokinetics (PK), i.e., absorption, distribution, metabolism, and renal excretion. This, in turn, influences optimal dosing, efficacy, and safety. To date, of the 40 H1-antihistamines available worldwide, only 11 have been studied in children using a PK approach. Here, we provide the pediatricians' perspective on the population PK of levocetirizine, the pharmacologically active enantiomer of cetirizine, in very young children who received oral cetirizine, and describe the factors that influence levocetirizine PK in this population. In a prospective, randomized, double-blind, parallel-group, placebo-controlled study, very young children received oral cetirizine 0.25 mg/kg twice daily for 18 months. Plasma levocetirizine concentrations were measured in timed, sparse blood samples collected at steady-state (3, 12 and 18 months after commencement of treatment) for the purpose of monitoring safety, and levocetirizine population, PK parameters were derived by using non-linear mixed effects modeling. In 343 children (age 14-46 months, body weight 8.2-20.5 kg), a total of 943 blood samples were obtained. Compliance with cetirizine dosing was documented. The population PK model used predicted that with increasing body weight, levocetirizine oral clearance would increase by 0.044 l/h/kg, and levocetirizine volume of distribution would increase by 0.639 l/kg. Levocetirizine PK were not influenced by eosinophilia, sensitization to allergens, allergic disease, gastroenteritis/diarrhea, or concomitant ingestion of other medications. This population PK model predicts that in very young children, the oral clearance of levocetirizine will be rapid and will increase as body weight and age increase, therefore, levocetirizine dosing should be based on body weight and age in this population. Compared with older patients, on a mg/kg basis, relatively higher doses may be needed, and twice-daily dosing may be necessary, as previously reported for the related racemic H1-antihistamine cetirizine.

Second-Generation Antihistamines

Antihistamines are useful medications for the treatment of a variety of allergic disorders. Second-generation antihistamines avidly and selectively bind to peripheral histamine H1 receptors and, consequently, provide gratifying relief of histamine-mediated symptoms in a majority of atopic patients. This tight receptor specificity additionally leads to few effects on other neuronal or hormonal systems, with the result that adverse effects associated with these medications, with the exception of noticeable sedation in about 10% of cetirizine-treated patients, resemble those of placebo overall. Similarly, serious adverse drug reactions and interactions are uncommon with these medicines. Therapeutic interchange to one of the available second-generation antihistamines is a reasonable approach to limiting an institutional formulary, and adoption of such a policy has proven capable of creating substantial cost savings. Differences in overall efficacy and safety between available second-generation antihistamines, when administered in equivalent dosages, are not large. However, among the antihistamines presently available, fexofenadine may offer the best overall balance of effectiveness and safety, and this agent is an appropriate selection for initial or switch therapy for most patients with mild or moderate allergic symptoms. Cetirizine is the most potent antihistamine available and has been subjected to more clinical study than any other. This agent is appropriate for patients proven unresponsive to other antihistamines and for those with the most severe symptoms who might benefit from antihistamine treatment of the highest potency that can be dose-titrated up to maximal intensity.

Cetirizine: a review of its use in allergic disorders

Cetirizine is a selective, second-generation histamine H1 receptor antagonist, with a rapid onset, a long duration of activity and low potential for interaction with drugs metabolised by the hepatic cytochrome P450 system. Cetirizine was generally more effective than other H1 receptor antagonists at inhibiting histamine-induced wheal and flare responses. Cetirizine is an effective and well tolerated agent for the treatment of symptoms of seasonal allergic rhinitis (SAR), perennial allergic rhinitis (PAR) and chronic idiopathic urticaria (CIU) in adult, adolescent and paediatric patients. In adults with these allergic disorders, cetirizine was as effective as conventional dosages of ebastine (SAR, PAR, CIU), fexofenadine (SAR), loratadine (SAR, CIU) or mizolastine (SAR). This agent was significantly more effective, and with a more rapid onset of action, than loratadine in 2-day studies in environmental exposure units (SAR). In paediatric patients, cetirizine was as at least as effective as chlorphenamine (chlorpheniramine) [SAR], loratadine (SAR, PAR) and oxatomide (CIU) in the short term, and more effective than oxatomide and ketotifen (PAR) in the long term. Cetirizine was effective in reducing symptoms of allergic asthma in adults and reduced the relative risk of developing asthma in infants with atopic dermatitis sensitised to grass pollen or house dust mite allergens. It had a corticosteroid-sparing effect in infants with severe atopic dermatitis and was effective in ameliorating reactions to mosquito bites in adults. Cetirizine was well tolerated in adults, adolescents and paediatric patients with allergic disorders. In adult, adolescent and paediatric patients aged 2-11 years, the incidence of somnolence with cetirizine was dose related and was generally similar to that with other second-generation H1 receptor antagonists. Although, its sedative effect was greater than that of fexofenadine in some clinical trials and that of loratadine or fexofenadine in a postmarketing surveillance study. In infants aged 6-24 months, the tolerability profile of cetirizine was similar to that of placebo. Cetirizine did not have any adverse effects on cognitive function in adults, or cognitive function, behaviour or achievement of psychomotor milestones in paediatric patients. Cetirizine was not associated with cardiotoxicity.

CONCLUSION

Cetirizine is well established in the treatment of symptoms of SAR, PAR or CIU. It demonstrated a corticosteroid-sparing effect and reduced the relative risk of developing asthma in sensitised infants with atopic dermatitis. Cetirizine was effective in the treatment of allergic cough and mosquito bites; however, its precise role in these indications has yet to be clearly established. On the basis of its favourable efficacy and tolerability profile and rapid onset of action, cetirizine provides an important option for the treatment of a wide range of allergic disorders.

Failure of Cetirizine to Prevent Nevirapine-Associated Rash

OBJECTIVES

Rash is the most frequent adverse event associated with nevirapine. The use of antihistamines remains unclear in this setting. A double-blind placebo-controlled study was performed to evaluate the efficacy of cetirizine in the prevention of nevirapine rash.

METHODS

A multicenter, randomized, double-blind, placebo-controlled clinical trial with cetirizine (10 mg/d x 30 days) was conducted. Inclusion criteria were HIV-1 infection and nevirapine therapy started with any CD4 cell count or plasma viral load and without simultaneous use of abacavir, cotrimoxazole, or rifampin. Clinical follow-up was performed at 15, 30, and 90 days.

RESULTS

Two hundred seventeen evaluable patients were enrolled (107 patients receiving cetirizine and 110 patients receiving placebo), 32.3% of whom were women. The median baseline CD4 cell count and plasma viral load were 341 cells/mm and 11,000 copies/mL, respectively. Overall, 29 rashes (13.4%) were detected: 16 (15.0%) in the cetirizine group and 13 (11.8%) in the placebo group (odds ratio [OR] = 1.31, 95% confidence interval [CI]: 0.60-2.88; P = 0.50). The incidence of moderate to severe rashes leading to nevirapine withdrawal was 10.3% (11 of 107 patients) in the cetirizine group and 7.3% (8 of 110 patients) in the placebo group (OR = 1.46, 95% CI: 0.52-4.18; P = 0.43). Adverse events leading to withdrawal of therapy appeared in 14 patients (13.1%) from the cetirizine group and 10 (9.1%) from the placebo group (P = 0.34).

CONCLUSION

Cetirizine does not prevent the incidence or affect the severity of nevirapine-associated rash.

H1-Antihistamines: more relevant than ever in the treatment of allergic disorders

Histamine is an important chemical mediator of inflammation, vasodilation, increased vascular permeability, decreased peripheral resistance, airway smooth muscle contraction, and sensory nerve stimulation causing itching. It also plays a significant role in neurotransmission and in cardiac function. In allergic rhinoconjunctivitis and urticaria, there is strong evidence for the role of H(1)-antihistamine treatment. In asthma, additional dose-response studies, including higher doses of antihistamines than those used in allergic rhinitis, are needed to determine the role of antihistamines. In atopic dermatitis, the itch-relieving topical glucocorticoid-sparing effects of H(1)-antihistamines also require further documentation. The potential benefits of each H(1)-antihistamine should be weighed against the potential risks, and second-generation H(1)-antihistamines with excellent, well-documented safety records should be used in preference to older, less safe H(1)-antihistamines. Second-generation H(1)-antihistamines are more relevant than ever in the treatment of allergic disorders.

Urticaria

Urticaria has been known as a disease since antiquity. However, in the last decades an increasing understanding of the mechanisms involved in its pathogenesis has shown the high heterogeneity of different urticaria subtypes. Clear distinction of the subtypes is required not only to choose the correct measures in diagnosis and management, but also to interpret the available data in research. The subtypes can be grouped into spontaneous urticaria, which includes acute urticaria and chronic urticaria, the physical urticarias, special types of urticaria including, e.g. contact urticaria, and diseases related to urticaria for historical reasons, e.g. urticaria pigmentosa. Most urticaria subtypes have a profound impact on the quality of life and effective treatment is thus required in case the diagnostic procedures do not reveal a cause which can be treated. Although, for symptomatic relief, nonsedating H1-antihistamines are the first choice in most subtypes of urticaria, double-blind controlled studies have shown that dosages required may exceed those recommended for other diseases, e.g. allergic rhinitis. Alternative treatments should be reserved for unresponsive patients.

Allergy-like asthma and rhinitis. A cross-sectional survey of a respiratory cohort and a diagnostic approach using the autologous serum skin test

BACKGROUND

Chronic idiopathic urticaria is considered an allergy-like skin disorder, and in some cases an auto-reactivity caused by mast cell degranulating factors has been demonstrated. A positive reaction to the autologous serum skin test (ASST), reflecting the presence of factors capable to degranulate the mast cells, is regarded as a reliable in vivo diagnostic test in chronic urticaria patients. About one out of three patients complaining for rhinitis or asthma does not show sensitization to any allergenic source. No data are available on the application of ASST to respiratory patients.

METHODS

A cohort of respiratory patients, aged 1 to 80 years, complaining about suspected respiratory symptoms was screened using a panel of inhalant allergens by means of SPT and IgE. Current and past information on skin and respiratory symptoms were recorded for each patient. Patients were divided in 'allergy' and 'allergy-like' whether or not they react to at least one allergenic source. Age and gender distribution were analyzed. A control group fulfilling criteria for chronic idiopathic urticaria (CIU) was selected as well. The ASST was applied to the control CIU group, to the allergy-like and allergy subsets, and to a group of 58 healthy adult subjects.

RESULTS

Allergy and allergy-like patients were differently distributed in relation to age and gender. Allergy-like children were prevalent before age six, whereas the prevalence of allergics steadily increased with age representing the large majority of patients in late childhood. The ratio of allergy/allergy-like subjects continues to increase in adult males, whereas adult females represent the large majority of the adult patients mainly within the allergy-like subset. Fifty-eight percent of CIU control patients reacted to the ASST. Among allergy-like patients ASST was positive in 47% of the adults (male 26%, female 54%), and in 84% of the children (no gender differences). The percentage of reactive subjects increased in the adult allergy-like subset if a CIU was associated (65%). Eighty-six percent of the pediatric patients and 61% of the adults having an allergy respiratory disease associated with an allergy-like condition had a positive ASST reactivity. Pure allergy patients reacted in 73% and 40% of the cases in the children and adults subgroups, respectively. Forty-five percent of healthy controls reacted to the ASST as well, and statistically significant gender differences were still recorded.

CONCLUSIONS

An ASST reactivity is reported for the first time in allergy-like respiratory patients. A higher prevalence of reactive subjects has been recorded in all the pediatric subsets without gender differences, whereas female reactivity is prevalent among adults. The ASST reactivity seems to parallel the patient distribution within the entire respiratory cohort. Further studies are needed to demonstrate that the serum factors causing the ASST reactivity in respiratory patients are the same as for CIU affected subjects. In the light of recent in vitro findings, the ASST reactivity of healthy subjects could lead to a new interpretation of the autologous serum reactivity.

Safety of cetirizine in infants 6 to 11 months of age: a randomized, double-blind, placebo-controlled study

BACKGROUND

H(1)-antihistamines are widely used for symptom relief in allergic disorders in infants and children; however, there are few prospective, randomized, double-blind, controlled studies of these medications in young children, and to date, no such studies have been conducted in infants.

OBJECTIVE

This prospective, randomized, parallel-group, double-blind, placebo-controlled study was designed to evaluate the safety of the H(1)-antihistamine cetirizine, particularly with regard to central nervous system and cardiac effects, in infants age 6 to 11 months, inclusive.

METHODS

Infants who met the entry criteria for age and had a history of treatment with an H(1)-antihistamine for an allergic or other disorder were randomized to receive 0.25 mg/kg cetirizine orally or matching placebo twice daily orally for 1 week.

RESULTS

The mean daily dose in cetirizine-treated infants was 4.5 +/- 0.7 mg (SD). No differences in all-cause or treatment-related adverse events were observed between the cetirizine- and placebo-treated groups. A trend was observed toward fewer adverse events and sleep-related disturbances in the cetirizine group compared with the placebo group. No prolongation in the linear corrected QT interval was observed in cetirizine-treated infants compared with either baseline values or with values in placebo-treated infants.

CONCLUSIONS

We have documented the safety of cetirizine in this short-term investigation, the first randomized, double-blind, placebo-controlled study of any H(1)-antihistamine in infants. Additional prospective, randomized, double-blind, placebo-controlled, long-term studies of cetirizine and other H(1)-antihistamines are needed in this population.

H1-antihistaminic activity of cetirizine and fexofenadine in allergic children

The clinical pharmacology of H1-antihistamines has not yet been optimally studied in children and other special groups of patients. Our objective was to determine the onset, extent, and duration of H1-antihistaminic activity of cetirizine and fexofenadine in the pediatric population. We performed a prospective, randomized, placebo-controlled, double-blind, crossover, single-dose study of these H1-antihistamines in 15 allergic children, mean+/-SEM age 8.8+/-0.5 years. We used suppression of the histamine-induced wheal and flare as the primary outcome. Compared with pre-dose baseline, cetirizine 10 mg suppressed the wheals significantly (p<or=0.05) from 2 to 24 h and the flares significantly from 1 to 24 h, achieving 77+/-SEM 10% to 86+/-9% suppression of the wheal from 2 to 7 h and 85+/-6% to 88+/-6% suppression of the flare from 2 to 24 h, inclusive. Compared with baseline, fexofenadine 30 mg did not suppress the wheals or flares significantly at any time, achieving 40+/-9% to 54+/-9% wheal suppression from 2 to 7 h and 45+/-11% to 68+/-9% flare suppression from 2 to 7 h, inclusive. Compared with placebo, cetirizine suppressed the wheals and flares significantly from 2 to 24 h. Compared with placebo, fexofenadine suppressed the wheals significantly at 4 and 6 h, and the flares from 4 to 7 h. Cetirizine suppressed the wheals and flares significantly more than fexofenadine at 2 h (wheals), and at 3 and 24 h (flares). Placebo did not suppress the wheals and flares significantly at any time. In children age 6-11 years, cetirizine 10 mg has a rapid onset of H1-antihistaminic activity, a 24-h duration of action, and greater H1-activity than fexofenadine 30 mg. Higher doses of fexofenadine should be tested in children.

Atopic dermatitis

Atopic dermatitis is a highly pruritic chronic inflammatory skin disorder affecting 10-20% of children worldwide. Symptoms can persist or begin in adulthood. It is also the most common cause of occupational skin disease in adults. This disease results from an interaction between susceptibility genes, the host's environment, pharmacological abnormalities, skin barrier defects, and immunological factors. New management approaches have evolved from advances in our understanding of the pathobiology of this common skin disorder.

Long-term treatment with cetirizine of infants with atopic dermatitis: a multi-country, double-blind, randomized, placebo-controlled trial (the ETAC trial) over 18 months

H1-receptor antagonists are considered central to the treatment of atopic dermatitis (AD)-associated pruritus and are widely used in the treatment of AD despite a lack of double-blind, randomized clinical trials. In this study we analyzed the effects of the long-term use of cetirizine on the severity, natural history, and treatment of AD. In the prospective, multi-country, double-blind, randomized, placebo-controlled Early Treatment of the Atopic Child (ETAC) study, 817 infants (12-24 months of age) who suffered from AD at study entry and with a history of atopic disease in a parent or sibling were treated for 18 months with either cetirizine (0.25 mg/kg) or placebo twice daily. All concomitant medications for the treatment of AD were allowed but had to be recorded by the investigator in the case report form; the concomitant use of H1-antihistamines was discouraged. The primary end-point for efficacy was the onset of asthma. Secondary parameters of efficacy, however, were the consumption of concomitant medications for AD (topical and systemic treatment) and the severity of symptoms related to AD, which was rated with the AD scale, SCORAD. The severity of AD, as measured by SCORAD, decreased significantly (p < 0.001) over the study period (18 months) in both groups. Other oral H1-antihistamines were significantly more often used in the placebo group than in the cetirizine group (24.9% vs. 18.6%, p = 0.03). The number of infants who developed urticaria during the study period was significantly lower with cetirizine treatment (placebo group: 16.2%; cetirizine group: 5.8%; p < 0.001). For the treatment of AD, mild topical corticosteroids (class I, e.g. hydrocortisone) were used in 41.6% of the patients (placebo group 41.6%, cetirizine group 41.7%) and moderate-to-potent topical corticosteroids (class II, III, IV) in 55.0% (respectively 56.4% and 53.5%). The duration of the use of topical moderate-to-potent corticosteroids differed between the cetirizine group and the placebo group (mean percentage of days: placebo 25.2, median 2.4; cetirizine mean 18.8, median 0.95 p = 0.067, Mann-Whitney test, not statistically significant). In sub-groups of infants with a SCORAD of >or= 25, this cortico-sparing effect was statistically significant (placebo 35.1 vs. 25.8 in the cetirizine group; p = 0.014, Mann-Whitney test). In conclusion, in view of the proven safety of cetirizine, the use of this drug might help to reduce the duration and the amount of moderate-to-strong topical corticosteroids used in the treatment of infants and children with AD. However, further studies designed with the primary end-point of AD are clearly indicated to confirm the benefits of the use of H1-antihistamines in the management of AD.

A double-blinded, randomized, placebo-controlled trial of cetirizine in preventing the onset of asthma in children with atopic dermatitis: 18 months' treatment and 18 months' posttreatment follow-up

BACKGROUND

Because asthma is not a curable condition, the development of strategies for prevention of the disease has a high priority. Atopic dermatitis is a common precursor to the development of asthma, and 2 studies have suggested that the use of an H(1) receptor antagonist might reduce the development of asthma while the treatment is being administered, at least in subgroups with evidence of high IgE levels. However, no trial to date has conducted follow-up after the initial treatment has been stopped to establish whether the intervention has merely suppressed symptoms or truly prevented disease.

OBJECTIVE

We sought to establish whether the use of cetirizine compared with placebo for 18 months in infants with atopic dermatitis suppressed or truly delayed the onset of asthma, even after cessation of therapy.

METHODS

The Early Treatment of the Atopic Child study was a double-blinded, parallel-group, randomized trial of 0.25 mg/kg body weight cetirizine administered twice daily compared with placebo given to infants between 1 and 2 years of age with atopic dermatitis. After 18 months of treatment, follow-up continued for a further 18 months. This article reports the outcome over the full 3 years of follow-up and relates the outcomes to the allergic status on the basis of IgE antibody measurements at recruitment.

RESULTS

Although there was no difference in cumulative prevalence of asthma between active and placebo treatment in the intention-to-treat population (P = .7), those infants with evidence of sensitivity to house dust mite, grass pollen, or both who were treated with cetirizine were significantly less likely to have asthma compared with those treated with placebo over the 18 months of treatment (P = .005 and .002, respectively), and this effect was sustained for the grass pollen-sensitized infants over the full 36 months (P = .008). In the house dust mite-sensitized group there was a gradual narrowing of the difference between active and placebo treatment in terms of cumulative prevalence of asthma at the end of 36 months but no evidence of a rebound immediately after the treatment stopped (P = .04). In the placebo population there was a significantly higher risk of development of asthma in those sensitized at baseline to egg (relative risk, 1.4 [95% CI, 1.1-1.7]), house dust mite (relative risk, 1.6 [95% CI, 1.3-1.9]), grass pollen (relative risk, 1.7 [95% CI, 1.4-2.1]), or cat (relative risk, 1.5 [95% CI, 1.2-1.9]). Early and persistent sensitization conferred a higher risk than transient or later sensitization.

CONCLUSIONS

Cetirizine compared with placebo truly delays or, in some cases, prevents the development of asthma in a subgroup of infants with atopic dermatitis sensitized to grass pollen and, to a lesser extent, house dust mite. Further studies are required focusing specifically on sensitized groups to substantiate this finding. The study also highlights risk factors for asthma in infants with atopic dermatitis and indicates that early and persistent aeroallergen sensitization confers a higher risk than later development of sensitivity.