A method of reducing the risk of embolization of peripheral blood vessels by providing a medical device having an expandable member having a drug coating layer which has a crystalline morphological form including a plurality of crystal particles of a water-insoluble drug regularly arranged and uniformly sized on the surface of the medical device, inserting the medical device in peripheral blood vessels, expanding the expandable member, pressing the drug coating layer to a blood vessel wall such that at least part of the plurality of crystal particles are transferred to the blood vessel wall, and deflating the expandable member such that the generation of microparticulates having a size that causes embolization of peripheral blood vessels is suppressed.