RESUMEN
PURPOSE: Study the radiolysis of solid-state metoclopramide hydrochloride at various absorbed doses. Elucidate the structure of the degradation products to gain information on the radiolysis mechanisms. METHODS: Solid-state metoclopramide samples were irradiated at several doses with gamma rays and high-energy electrons to evaluate the influence of the dose rate. High-performance liquid chromatography with a diode array detector was used to measure the chemical potency as a function of the absorbed dose and to quantify the degradation products. The characterization of degradation products was performed by liquid chromatography/atmospheric pressure chemical ionization/tandem mass spectrometry. RESULTS: The degradation of solid-state metoclopramide after irradiation was negligible. No qualitative or quantitative differences were observed between gamma and electron beam irradiations (no dose rate effect). Four degradation products that were similar to metoclopramide were detected in trace levels (below 0.1% of the drug concentration) and were not unique to irradiation because they were found in lower amounts in unirradiated metoclopramide. The major degradation product formed after radiation was due to the loss of the chlorine atom from the metoclopramide molecule. CONCLUSION: Solid-state metoclopramide is radioresistant from a chemical point of view and therefore could be a suitable candidate for radiosterilization studies by either gamma rays or high-energy electrons.
Asunto(s)
Antieméticos/efectos de la radiación , Electrones , Rayos gamma , Metoclopramida/efectos de la radiación , Antieméticos/química , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Espectrometría de Masas , Metoclopramida/química , Estructura Molecular , Esterilización/métodos , Tecnología Farmacéutica/métodosRESUMEN
Describimos una experiencia técnico-radiológica del Aparato Digestivo practicada en 250 pacientes mediante el uso de Metoclopramida oral. Efectuamos estudios dobles en cada paciente sin la droga y con ella a la dosis de 20 mgs., ingerida 30 minutos antes de tomar el contraste baritado. Se comprueba la atoxicidad y fácil uso del medicamento así como la reducción del tiempo para la exploración radiológica total del tracto digestivo y la mejor calidad de los estudios, eliminando en su mayor parte los factores que perturban el estudio del tránsito esofagastrointestinal