Multicentre, Randomized, Controlled Trial of Qideng Mingmu Capsule in The Treatment of Diabetic Retinopathy

Inclusion Criteria: * Diagnosed with non-proliferative diabetic retinopathy(NPDR)，differentiated as deficiency of Qi-Yin syndrome or blood stasis syndrome in traditional Chinese medicine(TCM). * best-corrected ETDRS visual acuity in study eye≥15 letters,or about 0.16(20/125) by the decimal point method. * Age between 30 and 70 years old. * Able and willing to give informed consent * Keep the level of blood sugar steady during the last three months before randomization, meanwhile the glucose lowering therapy could be predicted without any change during this study. * Eligible patients are with moderate and severe diabetic retinopathy primarily, mild of whom are controlled within 15%. * All procedures from participance in the study voluntarily, signature on the Informed Consent Form (ICF) and acceptance of treatment are according to GCP guidelines. Exclusion Criteria: * Patients with ineffective blood sugar control (HbAlc\>9%) or without usage of fundamental antidiabetic drugs such as biguanides, sulfonylureas (SUs), insulin and thiazolidinediones (TZDs). * Patients who have had intraocular surgery like retina photocoagulation within 6 month; or are appropriate for laser photocoagulation currently, on the condition that more than two quadrants have extensive non-perfusion areas. * Patients with other ophthalmological combined diseases like glaucoma, cataract that have effected the check of eyeground deeply, non-diabetic retinopathy, uveitis, retinal detachment, diseases of optic nerve, high myopia with eyeground pathological changes,etc. * Patients with severe cardiovascular diseases, functional disorders of liver and kidneys, diseases of the haematopoietic system (bone marrow hypoplasia, leucopenia, anemia, etc.), severely abnormal electrocardiogram (ECG), ALT\>2 \*ULN, Cr \>1.5\*ULN and psychopaths.-Patients with diabetic nephropathy (DN) in the stage of azotemia or uremia. * Pregnant women or trying to conceive or in lactation; patients with allergic constitution. * Patients who have participated in other clinical trials in recent one month. * Patients who have used the drugs in the treatment of diabetic retinopathy (calcium dobesilate, Difrarel, capsule of Xueshuantong, ginkgo biloba extract, Qiming granula, etc.) in past two weeks. * Patients with SBP\>160mmHg or DBP﹥100mmHg.