The effect of calcium dobesilate (Doxium) therapy on the evolution of diabetic retinopathy has been assessed in a retrospective study. 54 patients with diabetic retinopathy received calcium dobesilate (average 650 mg/day) for 6–30 months (average 18 months) and were compared to a correspondingly selected control group. The patients were divided into three subgroups (mild, moderate, and severe diabetic retinopathy). Microaneurysms, blot hemorrhages, striate hemorrhages, and hard exudates were assessed semiquantitatively from panorama fundus photographs, using a scoring system. The effect of calcium dobesilate was statistically significant for cases with moderate background diabetic retinopathy on summing up the scores of the various retinal lesions. There was no favorable effect on diabetic maculopathy or visual acuity. In the proliferative stages of diabetic retinopathy, photocoagulation is offering, in the majority of cases, the only chance to slow down the progression of this disease; however, drug therapy might be beneficial in nonproliferative diabetic retinopathy.