Development of a multiparticulate system containing enteric-release mini-tablets of omeprazole

The main aim of this study was to develop a multiparticulate system containing mini-tablets of omeprazole formulated with an enteric polymer with pH-dependent solubility. Pre-formulation studies showed good flow and compaction capacity, leading to the production ofhigh quality mini-tablets. The mini-tablets were coated in a fluidized bed with hydroxypropylmethylcellulose /Eudragit(r) L30D55 and packed into hard gelatin capsules. The dissolution profile showed gastro-resistance and zero-order kinetics. The dissolution profile for the formulation containing lactose as the diluent and coated with 12% (tablet weight gain) of polymer was similar to that ofthe reference drug.

O presente trabalho teve como objetivo desenvolver e avaliar um sistema multiparticulado de liberação modificada, composto por mini-comprimidos revestidos com polímero de liberação pH-dependente, utilizando como fármaco modelo o omeprazol. Os mini-comprimidos (diâmetro de 2,5 mm) foram obtidos em máquina de compresssão excêntrica, revestidos em leito fluidizado com hidroxipropilmetilcelulose/Eudragit(r)L30D55 e, em seguida, acondicionados em cápsulas gelatinosas duras. A partir dos resultados obtidos no perfil de dissolução foi possível demonstrar a liberação gastro-resistente e comportamento cinético de ordem zero. A formulação contendo lactose como diluente, com revestimento de 12% de polímero, demonstrou semelhança com o medicamento referência.

Farmacovigilancia activa en pacientes afiliados al sistema general de seguridad social en salud / Active pharmacosurveillance of patients affiliated to the Colombian general social security/health system

Objetivos Determinar los posibles resultados negativos asociados a la medicación mediante la metodología de búsqueda activa de posibles interacciones medicamentosas en bases de datos de pacientes afiliados al Sistema General de Seguridad Social en Salud. Métodos A partir de las bases de datos de dispensación de medicamentos de Audifarma S.A a unos 4 millones de usuarios del país, se hizo una revisión sistemática de estadísticas de una serie de medicamentos identificados por presentar interacciones de riesgo, dosis diferentes a las recomendadas o dispensación irregular. Los casos son socializados con las EPS responsables. Resultados Se encontró un caso de nefrotoxicidad por ácido zoledrónico; el 37,0 por ciento de los usuarios de clopidogrel recibían concomitantemente omeprazol, que reduce la efectividad del primero; el 29,9 por ciento de los pacientes que toman losartan están recibiendo dosis superiores a las recomendadas para su indicación; el 2,0 por ciento de los pacientes que toman metoprolol o verapamilo, los recibe simultáneamente, con riesgo de generar bradicardia sinusal, bloqueos auriculoventriculares o disfunción sistólica. Todos los casos fueron notificados a los responsables en la EPS que atienden estos pacientes. Discusión La farmacovigilancia activa permite optimizar recursos, prevenir eventos adversos que puedan potencialmente causar morbilidad importante o incluso letalidad o determinar problemas que podrían ser responsables del fracaso terapéutico. Este tipo de estrategia se anticipa a la aparición de posibles riesgos para el paciente por lo que se recomienda considerarla para reforzar los programas de vigilancia de uso de medicamentos en el país.

Objectives Determining negative results associated with medication through an active search of possible drug interactions in databases for patients affiliated to the Colombian general social security/health system. Methods Statistics related to Audifarma S.A. dispensation drug databases for about 4 million Colombian users were systematically reviewed for identifying drugs having known interactions involving risk, doses different from recommended ones or irregular dispensation. The pertinent health-care providing services were made aware of the above. Results There was one case of nephrotoxicity being caused by zoledronic acid. 37 percent of clopidogrel users concomitantly received omeprazole which reduces the former's effectiveness. 29.9 percent of patients who were taking losartan were receiving doses higher than the recommended ones. 2.0 percent of patients who were taking metoprolol or verapamil were simultaneously receiving them, at the risk of generating first-degree heart block, bradycardia, or systolic dysfunction. All these cases were notified to the pertinent health-care services. Conclusions Active pharmacosurveillance leads to resources being optimised, adverse events which can potentially cause morbidity or lethality being prevented or even determining problems which could be responsible for therapeutic failure. This type of strategy anticipates the appearance of possible risks for patients, meaning that drug use monitoring programmes in Colombia should be reinforced.

Interaction study between levofloxacin and omeprazole using urinary pharmacokinetic data

The objective of this study was to observe the drug interaction between levofloxacin and omeprazole using urinary excretion data. Levofloxacin tablet and omeprazole capsule were administered separately as well as in combination in fasting condition with a wash out period of two weeks after each administration. Urine was collected at different time intervals of 0, 0-2, 2-4, 4-8, 8-12, 12-24, 24-36 and 36-48 hr post-dose and analyzed using a validated HPLC with UV detection. Different pharmacokinetic parameters for both drugs were determined using non-compartmental method. The maximum rate of excretion [R[max]] of levofloxacin was not decreased significantly when co-administered with omeprazole [p>0.05]. Similarly no significant difference [p = 0.350] was observed for R[max] of omeprazole when co-administered with levofloxacin. Again the fraction of levofloxacin excreted [f[e]/f] was not changed significantly [p = 0.953] due to the co-administration of omeprazole. Similarly fraction of omeprazole excreted [f[e] /f] also remained unaffected [p = 0.672] when co-administered with levofloxacin. No significant change was observed for the area under the rate of excretion versus midpoint of time interval curve from zero to 48 hours [AURC[0-48] for levofloxacin and omeprazole [p = 0.816 and 0.792 respectively] when administered separately and co-administered with each other. The study clearly revealed that levofloxacin and omeprazole do not undergo any kind of interactions when administered together. So it can be concluded that these two drugs can be prescribed together to achieve optimum therapeutic activity

Alivio de la sintomatología ácido péptica, con omeprazol / Peptic symptmomatology relieve with omeprazole

El objetivo de este estudio multicéntrico fue investigar el efecto de omeprazol, 20 mg una vez al día, sobre la sintomatología ácido-péptica, durante un periodo de dos semanas de tratamiento. En el estudio participó un total de 621 pacientes con esofagitis por reflujo, úlcera duodenal, úlcera gástrica y gastritis. Al final del periodo de tratamiento, 70 por ciento de los pacientes informó estar libre de síntomas y el resto mostró marcada mejoría. Este resultado fue conformado por los médicos tratantes, quienes durante la evaluación clínica encontraron a 80 por ciento de los pacientes libre de síntomas. Omeprazol fue bien tolerado y la frecuencia de reacciones adversas fue de 3.5 por ciento, las que fueron leves y transitorias. Debido a la eficacia y tolerabilidad de omeprazol, fue preferido por 85 por ciento de los pacientes, quienes habían recibido otro tratamiento antiulceroso, principalmente con antagonistas H2. Se concluyó que omeprazol, 20 mg al día es rápido y altamente ficaz en el alivio de los síntomas relacionados con la enfermedad ácido-péptica, mostrando un grado de éxito terapéutico no observado con otros tratamientos antiulcerosos.