A catheter having a non uniform wall thickness comprising first and second wall regions is described. The first region is thicker than the second region and at least a part of the first region comprises a material having a lower stiffness modulus than the second region. Typically, the ratio of stiffness between the first region and the second region is less than 1.25:1 and preferably approximately 1:1. The first region may comprise the same material as the second region but having a different formulation so that the stiffness modulus is altered. Alternatively, the regions may comprise different materials. The lower modulus material is coextruded into at least a part of the broadest/thicker cross sectional region(s).