Hi, thanks for asking in Healthcare Magic. Clopidogrel is an anti platelet agent. It interferes with platelet function and prevents clotting. It is very effective in arterial thrombosis. Partial retinal artery occlusion is most often due to high BP or thrombosis/emboli (clot). The origin of thrombosis/ emboli would have been elsewhere and may not be in retinal artery itself. So much so, the treatment also needs to be focused on the clots generally rather than on retina itself and also the drugs that prevent clotting should be given lifelong. Clopidogrel will ensure an additional benefit in the prevention of other cardiovascular and cerebrovascular complications due to clotting (thrombosis). Although it would have been better if ECHO had been done to rule out the cardiac problem, there is no harm in starting Clopidogrel because it will also inhibit formation of clots in all arteries irrespective of the organs they supply All anti platelet agents cause bleeding, Bleeding time and Clotting time should be seen periodically to prevent bleeding episodes. I hope this is useful.