Vatous observations carried out in the course of the years have shown that certain neuropeptides have a possible role to play as inflammation mediators. The substances on which attention has been principally focused are: substance P, calcitonin gene-related peptide, capsaicin an histamine. Knowledge acquired in this field, however, does not yet permit us to sufficiently clarify the role, not to speak of the possible action mechanism, on the basis of which these neuropeptides act, although it is confirmed that these substances have been found first in laboratory animals and later also in human tissues in the course of experimentally induced neurogenic inflammation. The need to know more and more about inflammatory mechanisms and the increasingly complex possibilities offered by the application of technology in the field of medical research have led to many small advance in our knowledge of what is involved in inflammation. In fact it has been understood that behind the typical signs of inflammation (the famous four cardinal signs of Celsus: pain, redness, swelling, heat) no abstract entities or strange alchemies are concealed, but a series of well-known, classified substance, the so-called "inflammation mediators", namely a variety of substances of cellular or plasmatic origin united by the fact that exist, in stationary state conditions, in the form of inactive precursors, or sequestered in intracellular sites where they are unable to carry out their action. Following an inflammatory stimulus, they are activated, or their synthesis can be induced, or their release from intracellular sequestration sites in favoured; in any case they are stored in the disturbance district in concentrations that are such as to act on their respective targets, triggering event s that characterise the various stages of the inflammatory process.