Abstract: A tubing having unitary construction and having a single lumen portion, a multilumen portion and a transition portion therebetween. The single lumen is in fluid communication with each and every lumen comprising the multilumen portion. The tubing may be made in any desired length by means of extrusion. The outer surface of the tubing may be either smooth or grooved and have any desired cross-sectional geometry. Similarly, any of the lumens can be made to have a desired cross-sectional shape and size. Although the tubing can be made from any extrudable material, a preferred material is medical grade silicone elastomer. An extrusion apparatus and a method for making the tubing in a continuous process is described.