The indications for the use of antithrombotic therapy are evolving as new drugs become available or new indications or dosages are recommended for drugs already in use. This document reviews and updates the former one published in 1994. To that end, an exhaustive revision of the literature published in the last 15 years has been undertaken. Following the evidence based medicine dictates, and aiming to select all the relevant publications for each pathology, all studies were selected through MEDLINE, using the specified key words for each subject, and were filtered using the following steps: a) only randomized, controlled studies, meta-analysis, guidelines and review articles were chosen; b) then, the Best-Evidence and Cochrane Collaboration databases were consulted; c) finally, the evidence based medicine validation, relevance and applicability criteria were assessed for each publication. The use of antiaggregants and anticoagulants are given for the following conditions: a) prevention of deep vein thrombosis and pulmonary embolism; b) prevention of systemic emboli in patients with lone atrial fibrillation, atrial fibrillation associated or not with rheumatic heart disease, in patients with biological or mechanical cardiac valvular prostheses and in dilated cardiomyopathy; c) antithrombotic therapy in coronary heart disease and in coronary intervention; d) the interactions with oral anticoagulants and how to control these therapies are also discussed.