Calcium dobesilate: Pharmacological profile related to its use in diabeticretinopathy

Calcium dobesilate (Doxium(R)) is used in the treatment of diabetic retinop athy. Clinical studies show a slowdown of the progression of the disease af ter long-term oral treatment. The main action of the drug is related to a r eduction of microvascular permeability as measured by different parameters and methods (vitreous fluorophotometry, retinal haemorrhages, skin capillar y resistance, blood albumin leakage, blood viscosity) leading to improved v isual acuity. The pharmacological activity may be explained in part by the antioxidant properties of calcium dobesilate and its action on endothelium through the synthesis of nitric oxide, increasing the endothelium-dependent relaxation. The antioxidant effect was demonstrated in different in vitro and in vivo models by decreasing the peritoneal permeability in rats induce d by pro-oxidant substances. Moreover, vascular leakage was also decreased by calcium dobesilate in a reperfusion model in streptozotocin induced diab etic rats after ischaemia of the central artery of the retina. Doxium may a lso preserve vascular endothelial function by acting directly as antioxidan t to protect lipids from peroxidation.