Objective: to establish prevalence of use and features of antibiotics prescription in a external advisory service of a hospital of third level of the city of Bogota. Methods: observational and cross-sectional study. Is a consumption drug utilization study whit analysis about prescriptions features. A simple random sampling was made to select sample. Results: in 5.970 prescriptions it were found 826 (13.8%) whit at least one systemic antibiotic use. Most prescripts antibiotics were: Cephalexin, ciprofloxacin and amoxicillin. It were prescripts combinations of two antibiotics like claritromicin + amoxicillin and combinatios of three antibiotics in 0.5%. During the study time were prescripts 10.466,85 DDD and most prescripts were beta lactamics and quinilones. In relations whit prescriptions features, 100% have patient information and 98.7% of a physician, in relation whit the drug information, 99% were prescript in generic name, 86.3% have not administration way and 70.9% have not treatment duration. In general, prescriptioms are agree with hospital rulers, however, is necessary to include administration way and treatment duration. It were obtain first consumption and prescriptions indicators in the service and in this way there are reference to future assessment.