The acknowledgment of pain as a pathologic entity in its own right remains debated. Notwithstanding the data showing the burden of pain as a disease, an ultimate recognition of the pathologic nature of this condition is lacking. In this study, we analyze the notion of pain as a disease through an historical overview of its several conceptualizations and report the main evidence supporting this notion. We believe that a clear definition of pain as a disease is necessary, especially considering the enormous global burden of this condition. Indeed, the recognition of pain as a definite pathologic state is crucial to raise awareness about this neglected global health problem and to promote the exploration of new specific therapeutic approaches.