Cilostazol widens arteries that supply blood to the legs. Cilostazol also improves circulation by keeping platelets in the blood from sticking together and clotting. Cilostazol is used to treat the symptoms of intermittent claudication. This condition causes reduced blood flow to the legs, leading to pain while walking. Cilostazol improves your ability to walk longer distances without pain. Cilostazol may also be used for other purposes not listed in this medication guide.