A medical article, such as a catheter, is formed from a blend of polyurethane and synthetic polyisoprene (SPIR). The blended medical article is preferably selected and prepared to be relatively rigid at room temperature and relatively flexible at body temperature. An intermittent catheter made from the blend provides a degree of stiffness for its insertion into the patient at room temperature. The catheter becomes softer, and therefore more comfortable, at warmer temperatures (e.g., body temperature) which reduce discomfort after insertion. Optionally, the catheter or a portion thereof can have a hydrophilic coating as to avoid the need for external lubricants. Advantageously, the blended catheter can meet the stiffness, tensile strength, and coefficient of friction requirements of intermittent catheterization applications while avoiding the risk of toxic or allergic reactions in sensitive users.