The medicinal leech has a cylindrical, dorsoventrally flattened body divided into twenty six segments. The dorsal side is dark brown to black, bearing six longitudinal, reddish or brown stripes, and the ventral surface is speckled.
All members bear a posterior and anterior disk-shaped sucker.
The anterior sucker surrounds the oral opening where the teeth for incison are located. In addition, the medicinal leech has five pairs of eyes located on its front end. Food Habits Hirudo medicinalis is parasitic and the adults feed on the blood of mammals. It attaches to the host by means of its two suckers and bites through the skin of its victim. Simultaneously, the leech injects an anaesthetic so that its presence is not detected, and an anticoagulant in order for the incision to remain open during the meal.