Interacciones entre medicamentos y alimentos: aspectos actuales
M.ª TERESA SAN MIGUEL SÁMANO1 , EMILIO VARGAS CASTRILLÓN2 Y ALFREDO MARTÍNEZ HERNÁNDEZ3
RESUMEN Las interacciones entre medicamentos y alimentos pueden producir efectos negativos en la seguridad y eficacia del tratamiento farmacológico y en el estado nutricional delpaciente. Las interacciones pueden clasificarse en dos tipos, en función de cual de los dos sustratos (medicamento o alimento) se ve afectado por la presencia del otro. Asimismo, de acuerdo con el mecanismo por el que se producen, pueden ser físicoquímicas, farmacocinéticas y farmacodinámicas. Las interacciones pueden prevenirse mediante una actuación conjunta por parte del equipo de profesionalessanitarios. Palabras clave: Interacciones farmacológicas.— Interacciones medicamento – alimento
SUMMARY: Drug – food interactions: an update Drug - food interactions can produce negative effects in the safety and efficacy of drug therapy, as well as in the nutritional status of the patient. They can be classified in two types, depending on the substrate (drug or nutrient) that exerts its effect on theother. Regarding the mechanism of the interplay, they can be categorised as physico-chemical, pharmacokinetic or pharmacodynamic interaction.
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Agencia Española de los Medicamentos y Productos Sanitarios. Servicio de Farmacología Clínica. Hospital Clínico San Carlos. Departamento de Nutrición. Universidad de Navarra.
M. T. SAN MIGUEL
AN. R. ACAD. NAC. FARM.These interactions can be prevented by a coordinated action of the health care team. Key words: Drug interaction.— Drug – food interaction.— Drug – nutrient interaction Extensive summary Adverse drug reactions and iatrogenic diseases have been identified as relevant events leading to patients´ morbidity and mortality. In this context, drug - food interactions can produce negative effects in thesafety and efficacy of drug therapy as well as in the nutritional status of the patient. The proportion of adverse reactions due to drug – food interactions is unknown and, often, only in case that a serious adverse reaction is observed, this type of event receives the adequate attention. Drug – food interactions have been investigated since decades. The first reports describe potential changes in drugabsorption during concomitant food intake, as it is the case for tetracycline and isoniazide. Subsequently, relevant interactions were identified, such as the deficiency of vitamin B6 induced by isoniazide and the interaction between monoamine-oxidase inhibitors and the amine tiramine contained in fermented food, which leads to hypertensive events. However, it has been during the last decade whenthe number of publications about drug – food interactions has raised significantly. An update of drug - food interactions with potential clinical consequences was carried out. They can be classified in two types, depending on the substrate (drug or nutrient) that exerts its effect on the other. However, in some cases, both substrates can be affected. Occasionally, an interaction can have abeneficial effect, affecting the drug absorption when it is taken with a meal, which reduces its side effects leading to a correct drug intake; but the increase in drug concentration observed with other drugs can produce serious toxicity so that, the term «interaction» is usually associated with a potentially clinically negative effect. The main factors that influence the appearance of a drug – foodinteraction are considered: — The physico – chemical and enantiomorphic composition of the drug. — The time between the meal and the drug intake. — The amount and composition of the meal (mainly fat, protein and fiber). — The dose of the drug. The magnitude and the incidence of a certain drug – food interaction shows a high inter and intra- patient variability and, in a real situation, it is...