[Leech hirudo medicinalis: a therapeutic alternative available in Mexico]

Throughout history a diversity of therapeutic properties have been attributed to the leech Hirudo medicinalis, however, during the past twenty years its use has proven to be a practical and effective method for the relief of venous engorgement in reconstructive surgery. In Mexico this practice has been limited due to the lack of supply and to the time-consuming process of importation. Based on this need, the animal facilities of the Occidental Biomedical Research Center-IMSS in Guadalajara, Jalisco, has initiated a breeding and reproduction program of this species with the aim at improving its availability as a therapeutic device. The salivary gland of Hirudo medicinalis contains one of the most potent natural anticoagulants, known as hirudin, a histamine-like vasodilator, platelet aggregation inhibitors and highly specific proteases, all of which favor venous flow and turn this species into the most useful in the clinical setting. Nevertheless, it is important to know the potential risks of leech therapy since it has been associated with considerable morbidity when adequate precautions are not taken. This review exposes relevant aspects of the medicinal leech, the indications, mechanism of action and the protocol for this therapy.