Hirudo Medicinalis. Medical /Medicinal/ Leech MEDIUM SIZE. The medium leech is our third most popular product sold on Leeches.com. Nevertheless, this size leech is probably the most versatile in its use and application than all other size leeches. Preferred by Hirudotherapy patients for general overall use and placement all over different body parts. Medium sized leeches suck approximately 3 times more than small leeches and about twice less than large leeches. The after-affects of blood-oozing also lasts longer than small leeches, but not as long as when applying large ones. If kept at home and given proper care, leeches will be able to be re-used on the same patient, in just 3 to 5 months. Being slightly older, medium leeches are slightly more experienced and able to de-clot and thin the blood very well. They form a good, clean sucking channel and inject a good amount of bio-chemicals necessary for the job. Medium leaches are also good at improving tissue micro-circulation and re-building the capillary structures. Hirudotherapy leech applications using medium leeches involves a minimal amount of pain or discomfort, as compared to their small counterparts, as they are able to inject a good amount of Hirudin, Painkillers and Antibiotics, making hirudotherapy with them easier and more comfortable, as well fairly fast. Medium leeches are also easy to take care of, being more resilient, they have higher survival rates than smaller leeches and therefore live longer. They are also slower than them, and harder to run away or escape. A medium-sized Hirudo Medicinalis leech displays a good amount of instinct in sensing problem areas on the body that need therapy. Since medium leeches are so versatile, they can be used on virtually any part of the body, except for the most delicate parts (arms, face and inner-thighs, throat and neck). You can safely apply medium leeches near veins (hands and legs), as well as all over the legs and hands (making them ideal for treatment of varicose veins). They can be used for leech therapy all over the torso, back of the neck and internally on gums and cervix.