To analyze the visa application process and his activity at a tertiary hosipital.Descriptive study of the drug s visa activity during the period April 2011-April 2012. We designed a database and defined categories on the study variables: patients and recipes. For patients admitted to the Visa Unit, issues detected were recorded based on a previously established classification.6738 patients were included. They involved the visa of 8,465 recipes. The visa was applied to 170 drugs and nutrition products different, being the majority Tacrolimus. During this period, we detected a total of 420 incidents being the most frequent «No clinical document» (46.67%) and the «Formal completion errors» (28.57%).This work has allowed a more detailed analysis of the activity, the types of incidents and the identification of areas for improvement.