Growing concern for the possible adverse effects of homologous transfusions has stimulated the development of measures to reduce such transfusions to an absolute minimum. These measures may be classified in three groups: autotransfusion, non-pharmacological measures and pharmacological measures. The latter, whose advantages, disadvantages and applications are the subject of this review, contribute to an effective reduction in the risk of exposure to homologous blood in several types of surgery (cardiac, orthopedic, urologic, digestive, transplantation, etc.) through the following mechanisms. 1. Increased circulating blood mass through stimulation of erythropoiesis with erythropoietin, which increases preoperative hemoglobin values and/or accelerates their postoperative recovery. Moreover, this treatment increases pre-surgical deposits of autologous blood in elective surgery. 2. Reduction of perioperative bleeding through desmopressin, synthetic antifibrinolytics (tranexamic and ε-aminocaproic) conjugated estrogens or aprotinin, whose main adverse effect is increased risk of thrombosis. Aprotinin also exerts considerable antiinflammatory effects. 3. Increased oxygenation through the use of artifical oxygen carriers based on hemoglobin or perfluorocarbons, some of which are currently the object of phase II or III clinical trials. 4. Restoration of normovolemia through the use of crystalloid solutions (isotonic saline solution, Ringer's lactate, etc.) natural colloids (albumin) or synthetic colloids (dextrans, gelatins, hydroxyethyl aldimines.