Animals are often mentioned as ingredients in the medical cuneiform tablets. This paper summarizes several aspects implied by the study of Fauna in the frame of Mesopotamian medicine. It consists of a brief introduction, focusing on three main aspects: firstly, what we find in the Assyro-Babylonian medical texts regarding animals; then, we will make a short presentation of the Decknamen theorie, which assumes that some animal names could in fact designate plants. The consequences of such a hypothesis are examined along with our methods to prove or disprove this theory on a case-by-case study; finally, we will state preliminary conclusions about the use of animals and their products in the Assyro-Babylonian medicine.