Introduction: Adequate intestinal cleanliness is crucial to achieve optimal colonoscopy performance. Several bowel preparation (BP) schemes have been proposed, but there is still no consensus as regards which is the most suitable in paediatric patients.Objective: To describe the effectiveness, adherence, and adverse effects of BP protocols differentiated by age group in paediatric patients subjected to colonoscopy.Patients and Method: Prospective, study that included patients < 18 years subjected to colonoscopy. BP protocols differentiated by age group were indicated as follows: < 6 m (glycerine suppository); 6 m-3y 11 m (poly-ethylene-glycol (PEG 3350 without electrolytes); 4y-9y 11 m (PEG3350 without electrolytes + bisacodyl); 10 y-18 y (PEG 3350 with electrolytes). Demographic, clinical information, adherence and adverse effects were registered. Effectiveness was determined using a validated scale (Boston modified) during colonoscopy.Results: A total of 159 patients were included, of which 87 (55%) were males, and with a median age of 4 years (range 1 m-17 years). Seventy eight percent of patients achieved successful BP. The higher effectiveness was observed in the groups of < 6 m (96%) and 10-18 y (91%). Constipation was significantly more frequent (29%) in the 4 yo-9 yo 11 m in which lower effectiveness was observed (69%). Good adherence was observed in 87% of patients. Adverse effects were observed in a third of patients, although they were mild and did not lead to the suspension of the BP.Conclusions: Satisfactory results were achieved with the BP schemes used, with a successful BP being obtained in 4 out of 5 patients. Results were different between groups, which is probably related to previous bowel transit and indicated medicationIntroducción: La adecuada limpieza intestinal (LI) es fundamental para lograr el máximo rendimiento diagnostico durante una colonoscopia. Existen diversos esquemas de LI, y en pediatria aún no hay consenso respecto al más adecuado.Objetivo: Describir la efectividad, adherencia y efectos adversos de protocolos de LI diferenciados por edad en pacientes pediátricos sometidos a colonoscopia.Pacientes y Método: Estudio descriptivo que incluyo pacientes < 18 años sometidos a colonoscopia. Se aplicaron esquemas de LI diferenciados por edad: < 6 meses (supositorio de glicerina); 6 meses-3 años, 11 meses (polietilenglicol [PEG] 3.350 sin electrolitos); 4 años-9 años, 11 meses (PEG 3.350 sin electrolitos + bisacodilo); 10 años-18 años (PEG 3.350 con electrolitos). Se registraron datos demográficos, clínicos, adherencia y efectos adversos. La efectividad fue determinada durante colonoscopia de acuerdo con la escala previamente validada (Boston modificada).Resultados: Se incluyeron 159 pacientes, de los cuales 87 fueron varones (55%), mediana de edad de 4 años (rango un mes-17 años). Se logró LI exitosa en el 78% de los pacientes. La mayor efectividad se alcanzó en < 6 meses (96%) y 10-18 años (91%). El grupo de 4 años 9 años, 11 meses, que evidencio menor efectividad (69%) tuvo mayor proporción de estreñimiento previo (29%). Se obtuvo buena adherencia en el 87% de los pacientes. Se observaron efectos adversos en un tercio de los pacientes (especialmente en el grupo 10-18 años), que fueron leves y no determinaron la suspensión del medicamento.Conclusiones: Con los esquemas de preparación utilizados se lograron resultados satisfactorios, obteniendo LI exitosa en 4 de cada 5 pacientes. Los resultados difirieron entre grupos, lo que podría deberse, al menos en parte, al protocolo utilizado y al habito intestinal previo.