In accordance with various aspects of the invention, implantable and insertable medical devices are provided, which contain one or more polymeric regions. In one aspect, the polymeric regions comprise (a) a block copolymer that comprises a polyaromatic block and a polyalkene block admixed with (b) a sulfonated high Tg polymer. In another aspect, the polymeric regions comprise a block copolymer that comprises (a) a sulfonated polymer block and (b) fluorinated polymer block.
