The histamine H4 receptor antagonist 1-[(5-chloro-2,3-dihydro-1-benzofuran-2-yl)methyl]-4-methyl-piperazine(LINS01007) prevents the development of DSS-induced colitis in mice.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with growing incidence worldwide. Our group reported the compound 5-choro-1-[(2,3-dihydro-1-benzofuran-2-yl)methyl]piperazine (LINS01007) as H4R antagonist (pKi 6.2) and therefore the effects and pharmacological efficacy on a DSS-induced mice model of UC were assessed in this work. Experimental acute colitis was induced in male BALB/c mice (n = 5-10) by administering 3 % DSS in the drinking water for six days. The test compound LINS01007 was administered daily i.p. (5 mg/kg) and compared to control group without treatment. Body weight, water and food consumption, and the presence of fecal blood were monitored during 7-day treatment period. The levels of inflammatory markers (PGE2, COX-2, IL-6, NF-κB and STAT3) were also analyzed. Animals subjected to the acute colitis protocol showed a reduction in water and food intake from the fourth day (p < 0.05) and these events were prevented by LINS01007. Histological signs of edema, hyperplasia and disorganized intestinal crypts, as well as neutrophilic infiltrations, were found in control mice while these findings were significantly reduced in animals treated with LINS01007. Significant reductions in the levels of PGE2, COX-2, IL-6, NF-κB and STAT3 were observed in the serum and tissue of treated animals. The results demonstrated the significant effects of LINS01007 against DSS-induced colitis, highlighting the potential of H4R antagonism as promising treatment for this condition.

The effect of early radiofrequency turbinate reduction, intranasal steroid, and antihistamine H-1 on persistent allergic rhinitis: a randomized clinical trial

Abstract Objective: We aimed to evaluate the effect of radiofrequency turbinate reduction as an initial treatment on clinical improvement, inflammatory mediators, and remodeling process. Methods: Between July 2018- February 2020, 32 patients with moderate-severe persistent AR were randomly divided into 2 groups. Intervention group received radiofrequency turbinate reduction followed by intranasal steroid and Antihistamine H-1 (AH-1), control group received intranasal steroid and AH-1. Both groups were evaluated for clinical improvement (using visual analogue scale based on total nasal symptoms score, peak nasal inspiratory flow, and turbinate size using imageJ) after 4 and 8 weeks of treatment. Inflammatory mediators (ELISA from nasal secretions was performed to measure ECP, IL-5, and HSP-70) and remodeling markers (nasal biopsy followed by immunohistochemistry examination was performed to evaluate MMP-9, TIMP-1, and PAI-1) were evaluated in week 4. Results: Three patients dropped out of the study, resulting in 16 patients in intervention group and 13 patients in control group. At week 4, clinical response improved significantly in the intervention group compared to control group (Chi-Square test, p<0.05). Compared to control, intervention group experienced a reduction of IL-5 and no significant change in ECP level (Mann Whitney test, p>0.05). Reduction in the ratio of MMP-9/TIMP-1 were significantly higher in intervention group (unpaired t-test, p< 0,05). Meanwhile, increase in HSP-70 in the intervention group was slightly lower than in control group, but the difference with control group was not significant (Mann Whitney test, p>0.05). Conclusion: Early radiofrequency turbinate reduction followed by pharmacotherapy given to persistent moderate-severe AR patients give more improvement only in early clinical symptoms and reduce MMP-9/TIMP-1 ratio, thus it might be suggested as one of the adjuvant therapies for the management of moderate-severe persistent AR. However, further investigation with a larger sample size and longer follow-up period is needed. Level of evidence: 1B.

The effect of early radiofrequency turbinate reduction, intranasal steroid, and antihistamine H-1 on persistent allergic rhinitis: a randomized clinical trial.

OBJECTIVE: We aimed to evaluate the effect of radiofrequency turbinate reduction as an initial treatment on clinical improvement, inflammatory mediators, and remodeling process. METHODS: Between July 2018-February 2020, 32 patients with moderate-severe persistent AR were randomly divided into 2 groups. Intervention group received radiofrequency turbinate reduction followed by intranasal steroid and Antihistamine H-1 (AH-1), control group received intranasal steroid and AH-1. Both groups were evaluated for clinical improvement (using visual analogue scale based on total nasal symptoms score, peak nasal inspiratory flow, and turbinate size using imageJ) after 4 and 8 weeks of treatment. Inflammatory mediators (ELISA from nasal secretions was performed to measure ECP, IL-5, and HSP-70) and remodeling markers (nasal biopsy followed by immunohistochemistry examination was performed to evaluate MMP-9, TIMP-1, and PAI-1) were evaluated in week 4. RESULTS: Three patients dropped out of the study, resulting in 16 patients in intervention group and 13 patients in control group. At week 4, clinical response improved significantly in the intervention group compared to control group (Chi-Square test, p < 0.05). Compared to control, intervention group experienced a reduction of IL-5 and no significant change in ECP level (Mann Whitney test, p > 0.05). Reduction in the ratio of MMP-9/TIMP-1 were significantly higher in intervention group (unpaired t-test, p < 0,05). Meanwhile, increase in HSP-70 in the intervention group was slightly lower than in control group, but the difference with control group was not significant (Mann Whitney test, p > 0.05). CONCLUSION: Early radiofrequency turbinate reduction followed by pharmacotherapy given to persistent moderate-severe AR patients give more improvement only in early clinical symptoms and reduce MMP-9/TIMP-1 ratio, thus it might be suggested as one of the adjuvant therapies for the management of moderate-severe persistent AR. However, further investigation with a larger sample size and longer follow-up period is needed. LEVEL OF EVIDENCE: 1B.

Antimicrobial and antibiofilm activities of desloratadine against multidrug-resistant Acinetobacter baumannii.

Aim: The antimicrobial and antibiofilm activities of the antihistamine desloratadine against multidrug-resistant (MDR) Acinetobacter baumannii were evaluated. Results: Desloratadine inhibited 90% bacterial growth at a concentration of 64 µg/ml. The combination of desloratadine with meropenem reduced the MIC by twofold in the planktonic state and increased the antibiofilm activity by eightfold. Survival curves showed that combinations of these drugs were successful in eradicating all bacterial cells within 16 h. Scanning electron microscopy also confirmed a synergistic effect in imparting a harmful effect on the cellular structure of MDR A. baumannii. An in vivo model showed significant protection of up to 83% of Caenorhabditis elegans infected with MDR A. baumannii. Conclusion: Our results indicate that repositioning of desloratadine may be a safe and low-cost alternative as an antimicrobial and antibiofilm agent for the treatment of MDR A. baumannii infections.

Application of Heterocycles as an Alternative for the Discovery of New Anti-ulcer Compounds: A Mini-Review.

A peptic ulcer is a lesion located in the esophagus, stomach, and upper intestine, caused by an imbalance between acid secretion and the release of protective mucus. This pathology is prevalent in approximately 14% of the world population and is commonly treated with proton pump inhibitors and type 2 histaminergic receptor antagonists, however, these drugs present concerning side effects that may lead to gastric cancer. In this sense, this research aimed to present the main heterocyclics studied in recent years. The screening method for the choice of articles was based on the selection of publications between 2000 and 2021 present in the Science Direct, Web of Science, Capes, and Scielo databases, by using the descriptors ''new derivatives'', "heterocyclics" "antiulcerogenic", "gastroprotective" and "antisecretor". This research showed that the most used rings in the development of anti-ulcer drugs were benzimidazole, quinazoline, thiazole, and thiadiazole. The results also portray several types of modern in silico, in vitro and in vivo assays, as well as the investigation of different mechanisms of action, with emphasis on proton pump inhibition, type 2 histaminergic receptor blockers, potassium competitive acid blockers, type E prostaglandin agonism, anti-secretory activity and anti-oxidant action. Additionally, the review evidenced the presence of the nitrogen atom in the heterocyclic ring as a determinant of the potential of the compound. This research suggests new alternatives for the treatment of gastric lesions, which may be more potent and cause fewer side effects than the currently used, and tend to evolve into more advanced studies in the coming years.

The Novel H4R Antagonist 1-[(5-Chloro-2,3-Dihydro-1-Benzofuran-2-Yl)Methyl]-4-Methyl-Piperazine (LINS01007) Attenuates Several Symptoms in Murine Allergic Asthma.

BACKGROUND/AIMS: Histamine is an important chemical transmitter involved in inflammatory processes, including asthma and other chronic inflammatory diseases. Its inflammatory effects involve mainly the histamine H4 receptor (H4R), whose role in several studies has already been demonstrated. Our group have explored the effects of 1-[(2,3-dihydro-1-benzofuran-2-yl)methyl]piperazines as antagonists of H4R, and herein the compounds LINS01005 and LINS01007 were studied with more details, considering the different affinity profile on H4R and the anti-inflammatory potential of both compounds. METHODS: We carried out a more focused evaluation of the modulatory effects of LINS01005 and LINS01007 in a murine asthma model. The compounds were given i.p. (1-7 mg/kg) to ovalbumin sensitized BALB/c male mice (12 weeks old) 30 min before the antigen challenging, and after 24 h the cell analysis from the bronchoalveolar lavage fluid (BALF) was performed. The lung tissue was used for evaluation by western blot (COX-2, 5-LO, NF-κB and STAT3 expressions) and histological analysis. RESULTS: Treatment with the more potent H4R antagonist LINS01007 significantly decreased the total cell count and eosinophils in BALF at lower doses when compared to LINS01005. The expression of COX-2, 5-LO, NF-κB and STAT3 in lung tissue was significantly reduced after treatment with LINS01007. Morphophysiological changes such as mucus and collagen production and airway wall thickening were significantly reduced after treatment with LINS01007. CONCLUSION: These results show important down regulatory effect of novel H4R antagonist (LINS01007) on allergic lung inflammation.

Antileishmanial activity of H1-antihistamine drugs and cellular alterations in Leishmania (L.) infantum.

Leishmaniases are infectious diseases caused by protozoan parasites Leishmania and transmitted by sand flies. Drug repurposing is a therapeutic approach that has shown satisfactory results in their treatment. Analyses of antihistaminic drugs have revealed their in vitro and in vivo activity against trypanosomatids. In this way, this study evaluated the antileishmanial activity of H1-antihistamines and identified the cellular alterations in Leishmania (L.) infantum. Cinnarizine, cyproheptadine, and meclizine showed activity against promastigotes with 50% inhibitory concentration (IC50) values between 10-29 µM. These drugs also demonstrated activity and selectivity against intracellular amastigotes, with IC50 values between 20-35 µM. Fexofenadine and cetirizine lacked antileishmanial activity against both forms. Mammalian cytotoxicity studies revealed 50% cytotoxic concentration values between 52 - >200 µM. These drugs depolarized the mitochondria membrane of parasites and caused morphological alterations, including mitochondrial damage, disorganization of the intracellular content, and nuclear membrane detachment. In conclusion, the L. infantum death may be ascribed by the subcellular alterations followed by a pronounced decrease in the mitochondrial membrane potential, indicating dysfunction in the respiratory chain upon H1-antihistamine treatment. These H1-antihistamines could be used to explore new routes of cellular death in the parasite and the determination of the targets at a molecular level, would contribute to understanding the potential of these drugs as antileishmanial.

Etiology of chronic urticaria: the Ecuadorian experience.

BACKGROUND: The purpose of this study was to identify chronic urticaria (CU) etiologies and treatment modalities in Ecuador. We propose that the sample distribution fits the expected one, and that there is an association between the etiology and its treatment. METHODS: We performed a retrospective study involving 112 patients diagnosed with CU using a Checklist for a complete chronic urticaria medical history. Demographic and clinical variables were collected. The etiology of CU was classified using the EAACI/GA2LEN/EDF/WAO guideline. Descriptive analyses were performed for demographical and clinical variables. Chi square tests were applied to analyze the fit of distribution and the independence of variables. P values less than 0.05 were considered significant. RESULTS: Among all the patients, 76.8% were diagnosed with chronic spontaneous urticaria (CSU), of which 22.3% had a known etiology or possible exacerbating condition. Food allergy was identified as the most common accompanying condition in patients with CSU (10.7%) (p < 0.01).. On the other hand, 23.2% inducible urticarias (CIndU) were indentified; dermographism was the most common (10.7%) (p < 0.01).Regarding treatment regimens, sg-H1-antihistamines alone represented the highest proportion (44.6%). The combination of any H1-antihistamine plus other drug was a close second (42.0%) (p < 0.01). Almost 48% of CSUs of unknown etiology were treated with any antihistamine plus another drug. In patients with known etiology, sg-antihistamines alone (44.0%) was the most common management. In addition, 53.8% of CIndUs were treated with sg-antihistamines alone. Though, these associations were not statistically significant. CONCLUSION: CSU is the most frequent subtype of CU. Modern non-sedating antihistamines in licensed doses are the drug of choice. Nevertheless, a great proportion of patients require the addition of another type of medication.

Urticária crônica espontânea refratária aos anti-histamínicos: opção por ciclosporina / Antihistamine-refractory chronic spontaneous urticaria: opting for cyclosporine

Introdução: Anti-histamínico de segunda geração (AH1 2ªG) é o tratamento de escolha para pacientes com urticária crônica espontânea (UCE). Porém, cerca de 50% dos pacientes não responde a este tratamento. A ciclosporina é uma opção para os quadros mais graves. A ciclosporina tem propriedades imunossupressoras potentes, mas, apesar de sua eficácia, seu uso é limitado devido a diversos efeitos colaterais importantes. Objetivo: O objetivo deste estudo foi avaliar a resposta à ciclosporina em pacientes com UCE refratária aos anti-histamínicos. Método: Estudo retrospectivo baseado no prontuário eletrônico de pacientes com UCE refratária aos AH1 2ªG e que não responderam à introdução de outros medicamentos para controle da urticária. A ciclosporina foi indicada para todos os pacientes. A dosagem de D-dímero foi realizada em alguns pacientes. Resultados: Trinta pacientes participaram do estudo. Desses pacientes, 80% eram do sexo feminino, e a média de idade era de 42,8 anos. Previamente à introdução da ciclosporina, todos estavam em uso de AH1, 60% de AH2, 67% de montelucaste, 33,3% de hidroxicloroquina, e 56,7% de corticoide oral. A mediana de tempo de uso da ciclosporina foi de 11,5 meses. Em relação à eficácia, 40% dos pacientes apresentaram melhora dos sintomas, 40% não responderam ao tratamento, e em 20% dos pacientes a resposta não foi avaliada por suspensão da ciclosporina devido a efeitos colaterais, ou não foi introduzida devido a alterações clínicas ou laboratoriais prévias. Houve aumento dos níveis pressóricos em 9 pacientes (30%), e nefrotoxicidade em 5 pacientes (16,7%). Conclusões: Embora a ciclosporina seja uma boa opção terapêutica para pacientes com UCE refratária aos AH1, os efeitos colaterais são frequentes e devem ser monitorados.

Introduction: Second-generation antihistamines (sgAH1) are the treatment of choice for patients with chronic spontaneous urticaria (CSU). However, about 50% of the patients do not respond to this treatment. Cyclosporine is an option for more severe presentations. This drug has potent immunosuppressive properties. Despite its effectiveness, use is limited due to several serious side effects. Objective: The aim of this study was to assess response to cyclosporine in patients with antihistamine-refractory CSU. Method: This retrospective study was based on the electronic records of patients with sgAH1-refractory CSU who did not respond to the introduction of other drugs to control urticaria. Cyclosporine was indicated for all patients. D-dimer dosage was performed in some patients. Results: Thirty patients participated in the study. Of these, 80% were female and the mean age was 42.8 years. Prior to the introduction of cyclosporine, all patients were using AH1, 60% AH2, 67% montelukast, 33.3% hydroxychloroquine, and 56.7% oral corticosteroids. Median time of cyclosporine use was 11.5 months. Regarding efficacy, 40% of the patients showed improvement of symptoms, 40% did not respond to treatment, and in 20% response was not evaluated because the medication was withdrawn due to side effects or was not introduced based on previous clinical or laboratory abnormalities. There was an increase in blood pressure levels in 9 patients (30%) and nephrotoxicity in 5 (16.7%). Conclusions: Even though cyclosporine is a good therapeutic option for patients with AH1-refractory CSU, side effects are frequent and should be monitored.

Astemizole inhibits cell proliferation in human prostate tumorigenic cells expressing ether à-go-go-1 potassium channels.

Prostate cancer (PC) is the main cause of cancer mortality in men worldwide. Therefore, novel treatments for PC are needed. Ether à-go-go-1 (Eag1) potassium channels display oncogenic properties, and have been suggested as early tumor markers and therapeutic targets for different cancers. These channels are overexpressed in many human tumors including PC. Astemizole targets several molecules involved in cancer including Eag1 channels, histamine receptors and ABC transporters. Here we studied Eag1 mRNA expression and protein levels in the non-tumorigenic and non-invasive human prostate RWPE-1 cell line, and in the tumorigenic and highly invasive human prostate WPE1-NB26 cell lines. The effect of astemizole on cell proliferation and apoptosis was also studied. The human prostate cell lines RWPE-1 and WPE1-NB26 were cultured following the provider´s instructions. Eag1 mRNA expression and protein levels were studied by real time RT-PCR and immunocytochemistry, respectively. Cell proliferation and apoptosis were studied by a fluorescence AlamarBlue®  assay and flow cytometry, respectively. No difference in Eag1 mRNA expression was observed between the cell lines. However, high Eag1 protein levels were observed in the invasive WPE1-NB26 cells, in contrast to the weak protein expression in RWPE-1 cells. Accordingly, astemizole decreased cell proliferation at nanomolar concentrations only in the invasive WPE1-NB26 cells.  Our results suggest that astemizole may have clinical relevance for prostate cancer treatment in patients with high Eag1 protein levels.

Prediction of the Efficacy of Antihistamines in Chronic Spontaneous Urticaria Based on Initial Suppression of the Histamine- Induced Wheal.

BACKGROUND: Antihistamines are the first line of treatment for chronic spontaneous urticaria. However, there is no effective method to predict whether an antihistamine will have a beneficial clinical effect or not. OBJECTIVE: To assess whether the change in histamine-induced wheal and flare measurements 24 hours after administration of antihistamine can predict the efficacy of treatment. METHODS: We performed a multicenter, triple-blind, randomized study. Patients received a daily oral dose of cetirizine, fexofenadine, bilastine, desloratadine, or ebastine over 8 weeks. After 4 weeks, a higher dose of antihistamine was administered to patients who did not experience a clinical response. A histamine skin prick test was carried out at baseline and 24 hours after the first dose of antihistamine. Disease severity (Urticaria Activity Score [UAS]), response to the histamine skin prick test, and impact on the patient's quality of life (Dermatology Life Quality Index [DLQI]) were determined every 2 weeks. RESULTS: The study population comprised 150 patients (30 per group) and 30 controls. Twenty-four hours after administration of antihistamine, inhibition of the histamine wheal by >75% was significantly associated with better UAS and DLQI scores. The safety and efficacy of the 5 antihistamines were similar. After updosing, rates of disease control (DLQI score <5) increased from 58.7% to 76.7%. CONCLUSIONS: Measurement of the histamine-induced wheal can predict which patients will have a strong clinical response to antihistamines but has limited utility for identifying nonresponders. The clinical significance of these data could be relevant in the search for new urticaria treatment regimens.

Reversible dementia due to neurocysticercosis: improvement of the racemose type with antihistamines / Demência reversível por neurocisticercose: melhora da forma racemosa com o uso de anti-histamínicos

Infection of the human central nervous system (CNS) by the larvae of Taenia solium, termed neurocysticercosis (NCC), is endemic in most developing countries, where it is a major cause of acquired seizures and other neurological morbidity, including neuropsychiatric symptoms. However, despite its frequent manifestation, some findings, such as cognitive impairment and dementia, remain poorly understood. Less commonly, NCC may affect the ventricular system and subarachnoid spaces and this form is known as extraparenchymal neurocysticercosis. A particular presentation of the subarachnoid form is called racemose cysticercosis, which has a progressive pattern, frequently leads to hydrocephalus and can be life-threatening. Here we review a case of the racemose variety of cysticercosis, complicated by hydrocephalus and reversible dementia, with remission of symptoms after derivation and that remained stable with use of dexchlorpheniramine. We discuss the challenges in diagnosis, imaging findings, treatment and follow-up of this disease.

A infecção do sistema nervoso central (SNC) pela larva da Taenia solium, intitulada neurocisticercose (NCC) é endêmica na maior parte dos países "em desenvolvimento", onde é a principal causa de convulsão adquirida, além de outras morbidades neurológicas, entre elas, sintomas neuropsiquiátricos. No entanto, apesar de manifestações neuropsiquiátricas serem frequentes, alguns achados, tais como comprometimento cognitivo e demência, continuam a ser mal compreendidos. Menos frequentemente, NCC pode afetar o sistema ventricular e espaços subaracnóideos e esta forma é conhecida como NCC extraparenquimatosa. Uma apresentação particular subaracnóidea, chamada cisticercose racemosa, é encontrada mais raramente, evolui de forma progressiva, associada a hidrocefalia e pode levar a morte. Neste artigo revisamos um caso da variedade racemosa de NCC, complicada com hidrocefalia e demência reversível que evoluiu com remissão dos sintomas após derivação ventricular e permaneceu estável com uso de dexclorfeniramina. Discutimos os desafios no diagnóstico, achados de imagem, tratamento e acompanhamento desta forma de doença.

Reversible dementia due to neurocysticercosis: Improvement of the racemose type with antihistamines.

Infection of the human central nervous system (CNS) by the larvae of Taenia solium, termed neurocysticercosis (NCC), is endemic in most developing countries, where it is a major cause of acquired seizures and other neurological morbidity, including neuropsychiatric symptoms. However, despite its frequent manifestation, some findings, such as cognitive impairment and dementia, remain poorly understood. Less commonly, NCC may affect the ventricular system and subarachnoid spaces and this form is known as extraparenchymal neurocysticercosis. A particular presentation of the subarachnoid form is called racemose cysticercosis, which has a progressive pattern, frequently leads to hydrocephalus and can be life-threatening. Here we review a case of the racemose variety of cysticercosis, complicated by hydrocephalus and reversible dementia, with remission of symptoms after derivation and that remained stable with use of dexchlorpheniramine. We discuss the challenges in diagnosis, imaging findings, treatment and follow-up of this disease.

A infecção do sistema nervoso central (SNC) pela larva da Taenia solium, intitulada neurocisticercose (NCC) é endêmica na maior parte dos países "em desenvolvimento", onde é a principal causa de convulsão adquirida, além de outras morbidades neurológicas, entre elas, sintomas neuropsiquiátricos. No entanto, apesar de manifestações neuropsiquiátricas serem frequentes, alguns achados, tais como comprometimento cognitivo e demência, continuam a ser mal compreendidos. Menos frequentemente, NCC pode afetar o sistema ventricular e espaços subaracnóideos e esta forma é conhecida como NCC extraparenquimatosa. Uma apresentação particular subaracnóidea, chamada cisticercose racemosa, é encontrada mais raramente, evolui de forma progressiva, associada a hidrocefalia e pode levar a morte. Neste artigo revisamos um caso da variedade racemosa de NCC, complicada com hidrocefalia e demência reversível que evoluiu com remissão dos sintomas após derivação ventricular e permaneceu estável com uso de dexclorfeniramina. Discutimos os desafios no diagnóstico, achados de imagem, tratamento e acompanhamento desta forma de doença.

[Mexican guidelines on the diagnosis and treatment of urticaria]. / Guía Mexicana para el Diagnóstico y el Tratamiento de la Urticaria.

BACKGROUND: Urticaria is a disease that a fifth of the population shallsuffer once in a lifetime. Recent clinical guidelines have proposed some fundamental changes in the diagnosis and treatment of urticaria, making the development of a national, multidisciplinary guideline, with wide acceptability among different professional groups -both specialists and primary health care workers-, necessary in Mexico. MATERIAL AND METHOD: Internationally recognized tools for guidelinedevelopment were used. An interdisciplinary group of clinical experts (some of them knowledgeable in methodology of guideline development) determined the objectives and scope of the Evidence Based Clinical Practice Guideline with SCOPE. It was decided to adapt and transculturize international guidelines on the diagnosis and treatment of urticaria. With AGREE-II three high-quality guidelines (Zuberbier 2014, Sánchez-Borges 2012, Powell 2007) were selected to function as basic guidelines (BG). A set of Clinical Questions was formulated that lead to recommendations/suggestions, based on these BG, taking into account the cultural and economic background of Mexico, according to GRADE recommendation development. RESULTS: By a formal process of discussion and voting during several working-sessions, experts and first level healthcare physicians determined the wording of the final guideline, taking particularly care of developing a document, adjusted to the reality, values and preferences of the Mexican patients. The use of oral second generation, non-sedating antihistamines as first line treatment is emphasized. CONCLUSION: This document is an Evidence Based Clinical Practice Guideline for the diagnosis and treatment of acute and chronic urticaria, based on three, high quality, international guidelines. It was developed by a multidisciplinary group. Tables and algorithms make the guideline user-friendly for both, first line health care physicians and specialists.

Antecedentes: la urticaria es una enfermedad que padece una quinta parte de la población en algún momento de su vida. Las guías internacionales recientes han propuesto unos cambios de fondo en su diagnóstico y tratamiento, por lo que había la necesidad de crear una guía nacional y multidisciplinaria, con base amplia en los gremios de especialistas y médicos de primer contacto en México. Material y método: un grupo interdisciplinario de expertos clínicos y algunos expertos en metodología determinó los objetivos y alcances de la Guía de Práctica Clínica Basada en Evidencia con el instrumento SCOPE. Se decidió llevar a cabo la adaptación y transculturización de guías internacionales para el diagnóstico y tratamiento de urticaria. Con el instrumento AGREE-II se seleccionaron las tres guías de alta calidad, como guías base (Zuberbier 2014, Sánchez-Borges 2012, Powell 2007) para formular y contestar la preguntas clínicas clave, en el contexto cultural y económico mexicano, según el método de desarrollo de recomendaciones GRADE. Resultados: mediante un proceso formal de discusión y votación durante varias juntas de expertos, se terminó la redacción de la forma final de la guía, con especial cuidado de lograr un ajuste a las realidades, valores y preferencias de los pacientes de México. Se hace hincapié en la administración de antihistamínicos vía oral de segunda generación, como tratamiento de primera elección. Conclusión: este documento es una Guía de Práctica Clínica Basada en Evidencia para el diagnóstico y tratamiento de urticaria aguda y crónica, basada en tres guías internacionales de alta calidad. Se desarrolló por un grupo multidisciplinario. Los cuadros y algoritmos hacen a la guía amigable para su uso por médicos de primer contacto y por especialistas.