Hydrea is a prescription medication presented in capsule form, with each capsule containing 500mg of hydroxyurea, its active ingredient. It is primarily prescribed for the management of chronic myeloid leukemia (CML), a cancer that impacts the production of white blood cells. In addition to its therapeutic use in CML, it also goes by the names Hydab, Cytodrox, and Myelostat, depending on the market and manufacturer.