Hydrogen-bonding synthons in lamotrigine salts: 3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazin-2-ium 2-[(2-carboxyphenyl)disulfanyl]benzoate in its monohydrate and anhydrous forms.

Lamotrigine is a drug used in the treatment of epilepsy and related convulsive diseases. The drug in its free form is rather inadequate for pharmacological use due to poor absorption by the patient, which limits its bioavailability. On the other hand, the lamotrigine molecule is an excellent hydrogen-bonding agent and this has been exploited intensively in the search for better formulations. The formulation presently commercialized (under the brand name Lamictal) is rather complex and includes a number of anions in addition to the active pharmaceutical ingredient (API). The title salts of lamotrigine, namely 3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazin-2-ium 2-[(2-carboxyphenyl)disulfanyl]benzoate monohydrate, C9H8Cl2N5+·C14H9O4S2-·H2O, (I), and the anhydrate, C9H8Cl2N5+·C14H9O4S2-, (II), contain a lamotriginium cation (L), a hydrogen dithiodibenzoate monoanion (D) and, in the case of (I), a disordered solvent water molecule. Both L and D present their usual configurations severely twisted around their central C-C and S-S bonds, respectively. The supramolecular structure generated by the many available donor and acceptor sites is characterized by a planar antisymmetric motif of the form D-L-L-D, i.e. the structural building block. Although this characteristic motif is extremely similar in both structures, its conformation involves different donors and acceptors in its R22(8) central L-L homosynthon. The lateral R22(8) D-L heterosynthons are, on the other hand, identical. These substructures are further connected by strong hydrogen bonds into broad two-dimensional structures, in turn weakly linked to each other. Even if the homo- and heterosynthons in (I) and (II) are rather frequent in lamotrigine structural chemistry, the composite tetrameric synthon appears to be much less common. The occurrence of these motifs among lamotrigine salts and cocrystals is analyzed.

Demonstration project on epilepsy in Brazil: situation assessment

PURPOSE: To provide a situation assessment of services for people with epilepsy in the context of primary health care, as part of the Demonstration Project on Epilepsy in Brazil, part of the WHO/ILAE/IBE Global Campaign 'Epilepsy out of the shadows'. METHODS: We performed a door-to-door epidemiological survey in three areas to assess the prevalence of epilepsy and its treatment gap. We surveyed a sample of 598 primary health care workers from different regions of Brazil to assess their perceptions of the management of people with epilepsy in the primary care setting. RESULTS: The lifetime prevalence of epilepsy was 9.2/1,000 people [95 percent CI 8.4-10.0] and the estimated prevalence of active epilepsy was 5.4/1,000 people. Thirty-eight percent of patients with active epilepsy were on inadequate treatment, including 19 percent who were taking no medication. The survey of health workers showed that they estimated that 60 percent of patients under their care were seizure-free. They estimated that 55 percent of patients were on monotherapy and that 59 percent had been referred to neurologists. The estimated mean percentage of patients who were working or studying was 56 percent. Most of the physicians (73 percent) did not feel confident in managing people with epilepsy. DISCUSSION: The epidemiological survey in the areas of the Demonstration Project showed that the prevalence of epilepsy is similar to that in other resource-poor countries, and that the treatment gap is high. One factor contributing to the treatment gap is inadequacy of health care delivery. The situation could readily be improved in Brazil, as the primary health care system has the key elements required for epilepsy management. To make this effective and efficient requires: i) an established referral network, ii) continuous provision of AEDs, iii) close monitoring of epilepsy management via the notification system (Sistema de Informação da Atenção Básica - SIAB) and iv)...

OBJETIVO: Avaliar a situação da assistência à epilepsia no contexto da atenção primária sob o Projeto Demonstrativo em epilepsia no Brasil, parte da Campanha Global Epilepsia Fora das Sombras da WHO/ILAE/IBE. MÉTODO: Fizemos um levantamento epidemiológico para definir a prevalência e lacuna de tratamento em epilepsia. Avaliamos a percepção de 598 profissionais de saúde da atenção básica de diferentes regiões do Brasil sobre epilepsia e seu manejo na rede básica de saúde. RESULTADOS: A prevalência acumulada de epilepsia foi de 9,2/1000 pessoas (95 por centoIC= 8,4-10) e a prevalência estimada de epilepsia ativa foi de 5,4/1000 pessoas. Trinta e oito porcento dos pacientes com epilepsia ativa estavam sendo tratados inadequadamente, incluindo 19 por cento que estavam sem medicação. A enquete com os profissionais de saúde mostrou que a média estimada de pacientes livre de crises sob os cuidados dos mesmos era de 60 por cento. A média estimada de porcentagem em monoterapia era de 55 por cento. A média estimada de porcentagem de referência para neurologistas era de 59 por cento. A média estimada de porcentagem de pacientes que estavam trabalhando ou estudando era de 56 por cento. A maioria dos médicos não se sente confiante em atender uma pessoa com epilepsia. DISCUSSÃO: A análise situacional da Fase I - estudo epidemiológico nas áreas de interesse do PD mostrou que a prevalência da epilepsia é similar a outros países em desenvolvimento e a lacuna de tratamento é grande. Um dos fatores importantes para a lacuna de tratamento é a falta de adequação à assistência na atenção básica. Essa situação pode ser revertida no Brasil, pois os elementos chaves existem na rede básica para o manejo de pessoas com epilepsia. Entretanto, para torna efetivo e eficiente é preciso i) estabelecimento de um sistema de referência e contra-referência, ii) fornecimento contínuo de medicação anti-epiléptica, iii) monitorização de manejo de pessoas com epilepsia através...

Demonstration project on epilepsy in Brazil: outcome assessment

PURPOSE: To assess the outcome of patients with epilepsy treated at primary care health units under the framework of the demonstration project on epilepsy in Brazil, part of the WHO/ILAE/IBE Global Campaign Against Epilepsy. METHOD: We assessed the outcome of patients treated at four primary health units. The staff of the health units underwent information training in epilepsy. The outcome assessment was based on: 1) reduction of seizure frequency, 2) subjective perception from the patients and the physicians point of view, 3) reduction of absenteeism, 4) social integration (school and work), and 5) sense of independence. RESULTS: A total of 181 patients (93 women - 51 percent) with a mean age of 38 (range from 2 to 86) years were studied. The mean follow-up was 26 months (range from 1 to 38 months, 11 patients had follow-up of less than 12 months). Seizure frequency was assessed based on a score system, ranging from 0 (no seizure in the previous 24 months) to 7 (>10 seizure/day). The baseline median seizure-frequency score was 3 (one to three seizures per month). At the end of the study the median seizure-frequency score was 1 (one to three seizures per year). The patients and relatives opinions were that in the majority (59 percent) the health status had improved a lot, some (19 percent) had improved a little, 20 percent experienced no change and in 2 percent the health status was worse. With regard to absenteeism, social integration and sense of independence, there were some modest improvements only. DISCUSSION: The development of a model of epilepsy treatment at primary health level based on the existing health system, with strategic measures centred on the health care providers and the community, has proved to be effective providing important reductions in seizure frequency, as well as in general well being. This model can be applied nationwide, as the key elements already exist provided that strategic measures are put forward...

OBJETIVO: Avaliar o resultado do tratamento de pacientes com epilepsia na atenção básica sob o modelo proposto pelo Projeto Demonstrativo no Brasil, como parte da Campanha Global Contra a Epilepsia da WHO/ILAE/IBE. MÉTODO: Avaliamos o resultado do tratamento nos pacientes acompanhados em quatro unidades básicas de saúde. As equipes de saúde fizeram um treinamento padrão. O resultado do tratamento foi baseado em cinco aspectos: 1) redução da freqüência das crises, 2) percepção subjetiva dos pacientes e dos médicos, 3) redução de absenteísmo, 4) integração social (escola, trabalho), e 5) senso de independência. RESULTADOS: Um total de 181 pacientes (93 mulheres - 51 por cento), com uma média de 38 anos (variando de 2 a 86 anos) entraram nesta análise. O tempo médio de seguimento foi de 26 meses (variou de 1 a 38 meses, 11 pacientes tinham seguimento menos de 12 meses). A freqüência das crises foi categorizada variando de 0 (sem nenhuma crise nos últimos 24 meses) a 7 (>10 crises/dia). O escore mediano da freqüência de crises no começo era de 3 (uma a três crises por mês). O escore mediano da freqüência de crises no final era de 1 (uma a três crises por ano). A opinião dos pacientes e familiares é que a maioria (106 casos) houve uma melhora importante na saúde, 34 tiveram pouca melhora, 37 não tiveram mudanças e em quatro houve piora. Em relação ao absenteísmo, integração social e senso de independência houve pouca melhora. DISCUSSÃO: O modelo desenvolvido de tratamento de epilepsia na atenção primária com base na estrutura de saúde existente, com estratégias centradas nos profissionais de saúde e na comunidade, provou ser efetivo com redução importante na freqüência das crises bem como na melhora em geral da saúde. Esse modelo pode ser aplicado em âmbito nacional, pois os elementos chaves já existem, desde que essas estratégias sejam pactuadas com os organismos locais de saúde.