Eliglustat hemitartrate is primarily used in the treatment of Gaucher disease type 1, a genetic disorder where fatty substances accumulate in cells and organs. It works by inhibiting the enzyme glucosylceramide synthase, which reduces the production of glucosylceramide, the substance that builds up in Gaucher disease. This helps to alleviate symptoms such as enlarged liver and spleen, anemia, and bone abnormalities. It is particularly beneficial for patients who cannot tolerate enzyme replacement therapy. The oral administration of eliglustat hemitartrate offers a convenient treatment option, improving the quality of life for patients with this chronic condition.