The drug being tested in this study is low doses of Optina (formerly known as Danazol) (DMI-5207) that may be an effective treatment for diabetic retinopathy and diabetic macular edema (DME). Laboratory studies have demonstrated that low doses of this drug may treat diabetic retinopathy and diabetic macular edema by two important ways, decreasing blood vessel permeability (related to leaking and edema) and by decreasing the formation of new leaky blood vessels. Optina is not approved by Health Canada for the treatment of diabetic macular edema but higher doses of Optina are approved by Health Canada for treatment of endometriosis (growth of cells similar to those that form inside of the womb that grows outside of the womb) and fibrocystic breast disease (a condition of the breast tissue). Higher doses of Optina have also been approved in the United States and many other countries since the mid-1970s in the treatment of men and women with hereditary angioedema (a disease which causes swelling in parts of the body) in addition to endometriosis and fibrocystic breast disease in women.