Medical processes ranging from epidemiological aspects of medicine to medical therapy can be significantly affected by the primary mechanisms of epigenetics consisting of DNA methylation, histone modifications, and noncoding RNA. It is now apparent that many medical disorders have a component of epigenetics that contributes to their pathology and epigenetic mechanisms can influence numerous aspects of medical management such as diagnosis, disease progression, and prognosis of medical disorders. The immune, gastrointestinal, cardiovascular, and reproductive systems as well as many others can be affected by epigenetic aberrations that lead to disease manifestations. In addition, multisystem disorders such as those relevant to infections, pediatrics, and metastasis as well as numerous others are also very important to the expression and manifestation of epigenetic diseases. The advent of epigenetic approaches to medical therapy has advanced significantly and this very small field has now grown to include new DNA methylation, histone deacetylase, and histone acetylase inhibitors as well as the development of epigenetic-based RNA molecules for therapy. These approaches are being developed for applications for the management of pain and precision medicine and may have future roles in stem cells as well as regenerative medicines. The many applications of clinical epigenetics have significantly expanded and are most likely secondary to the importance that this discipline has in the vast field of health care.