Megestrol acetate is a synthetic progestin medication primarily used to treat breast and endometrial cancers as well as appetite loss and wasting syndrome in HIV patients. Other names for megestrol acetate include megestrol, MGA, megestin, and Ovaban. Megestrol acetate is available in both oral and injectable forms. It works by blocking the production of estrogen, which helps to slow the growth of breast and endometrial cancers. It is commonly used in conjunction with other cancer treatments such as radiation and chemotherapy. However, it is essential to note that megestrol acetate is not recommended for use during pregnancy.