Cytoxan is used to treat cancer of the ovaries, breast, blood and lymph system, nerves (found primarily in children), retinoblastoma (a cancer of the eye found primarily in children), multiple myeloma (cancer in the bone marrow), and mycosis fungoides (tumors on the skin).
Hydrea (Hydroxyurea) is used to treat melanoma, chronic myelocytic leukemia, ovarian and primary squamous cell cancer, carcinoma of the head and neck (excluding the lip), chronic myelogenous leukemia, sickle cell anemia.