Naftidrofuryl oxalate works in two main ways. firstly, it causes the blood vessels to widen. secondly, it increases the ability of cells to remove waste products.in peripheral vascular diseases, the blood vessels in the extremities are narrowed and the blood and oxygen supply to cells in the hands, feet or legs is reduced. oxygen is required by cells in order for them to remove waste products, therefore in these conditions waste products can build up. this can cause damage to cells and lead to symptoms such as pain, cramps or ulceration.naftidrofuryl improves these symptoms by increasing blood and oxygen supply to the affected areas and also increasing the ability of the cells to remove waste products.