Venous thromboembolism (VTE) is a prevalent and serious complication in hospitalized medical patients. Pulmonary embolism is the most common preventable cause of hospital death. VTE extends hospitalization, with a higher resource consumption and an increase in healthcare costs. Risk factors for VTE include intrinsic factors and those related to hospitalization. It is important to know and to identify these factors at the moment of hospital admission and during the course of disease. VTE prophylaxis has demonstrated to be an efficient and effective action. Its implementation reduces life-threatening pulmonary embolism, symptomatic deep vein thrombosis and death rate three months after discharge. An individual and detailed assessment of prophylaxis risk-benefit is a priority. In our country, low molecular weight heparins are still the first option for VTE pharmacological prophylaxis. In those patients at high risk of bleeding or in whom anticoagulation is contraindicated mechanical methods could be used.Copyright © 2020 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.