ResumenIntroducción. La prescripción inapropiada de medicamentos es un problema reconocido, al cual los ancianos son una población vulnerable.Objetivo. Describir la medicación potencialmente inapropiada en ancianos atendidos en consulta ambulatoria en un hospital de cuarto nivel de Bogotá en 2007. Materiales y métodos.Se hizo un estudio de corte transversal. Como criterios de medicación potencialmente inapropiada en ancianos se utilizaron los propuestos por Beers, actualizados en 2002. La información se obtuvo de la última consulta registrada en la historia clínica en 2007, de una muestra de 420 ancianos que asistieron a consulta ambulatoria en un hospital de cuarto nivel.Resultados. El promedio de medicamentos prescritos fue de 3,2. El 61,95% de los pacientes recibía múltiples medicamentos. Los grupos de medicamentos más Palabras clave: anciano, prescripción de medicamentos, salud pública, farmacoepidemiología, utilización de medicamentos. TitlePotentially inappropriate medications in the elderly in a fourth level care hospital in Bogotá Abstract Background: The prescription of inappropriate medications is a recognized problem, to which the elderly are a vulnerable population.Objective: To describe the potentially inappropriate medications in the elderly (PIME) treated at outpatient consultation in a fourth-level hospital in Bogota in 2007. Materials and methods:A cross-sectional study was developed, updated in 2002 Beers criteria were used as PIME. The information was obtained from the last record in the medical history in 2007, from a sample of 420 outpatient elderly people in a fourth-level hospital. Results:The average number of drugs prescribed was 3.2. 61.95% of the patients were polymedicated. Drug groups most frequently prescribed were those acting on the cardiovascular system (34.7%), alimentary tract and metabolism (18.1%) and nervous system (14.6%). PIME was received by 20.7% of patients according to Beers criteria. PIME was associated with polypharmacy. PIME was more frequent in patients with diagnoses of circulatory system diseases and with action on the nervous system. Drugs that can cause problems not classified as PIME by Beers were prescribed to 15% of patients.Conclusions: PIME is a frequent problem, it is necessary to adapt and supplement the Beers criteria to different context.