An apparatus to aid in inserting a guidewire into a guidewire lumen of a catheter, the apparatus comprising: a pliable loading coupler having a catheter insertion end, a guidewire insertion end, and a continuous lumen extending therebetween, wherein in a distal section of the loading coupler a diameter of the lumen tapers from the guidewire insertion end in a proximal direction to receive and direct a proximal end of the guidewire into the apparatus, wherein in a proximal section of the loading coupler the diameter of the lumen tapers from the catheter insertion end of the loading coupler in a distal direction to receive and couple with a correspondingly tapered distal tip of the catheter, wherein the tapered proximal section (110, 910) of the loading coupler includes a circumferential protrusion or rib formed on an inner surface of the loading coupler, the protrusion or rib configured for mating a circumferential groove or channel formed on an outer surface of the conical distal tip of the catheter, or the tapered proximal section (110, 910) of the loading coupler includes the circumferential groove or channel formed on the inner surface of the loading coupler, configured for mating the circumferential protrusion or rib formed on the outer surface of the conical distal tip of the catheter, and wherein in a middle section of the pliable loading coupler the diameter of the lumen is constant and wherein the straight middle section of the lumen connects the tapered distal and proximal sections of the lumen to straighten and stabilize the guidewire received from the distal section of the lumen prior to entry of the guidewire into the guidewire lumen of the catheter being held in the proximal section of the lumen; a longitudinally-extending area of weakness formed along a length of the pliable loading coupler; and a tab radially extending from the pliable loading coupler, wherein the tab is adapted to be gripped by a user in order to remove the pliable loading coupler from the catheter via the area of weakness. a pliable loading coupler having a catheter insertion end, a guidewire insertion end, and a continuous lumen extending therebetween, wherein in a distal section of the loading coupler a diameter of the lumen tapers from the guidewire insertion end in a proximal direction to receive and direct a proximal end of the guidewire into the apparatus, wherein in a proximal section of the loading coupler the diameter of the lumen tapers from the catheter insertion end of the loading coupler in a distal direction to receive and couple with a correspondingly tapered distal tip of the catheter, wherein the tapered proximal section (110, 910) of the loading coupler includes a circumferential protrusion or rib formed on an inner surface of the loading coupler, the protrusion or rib configured for mating a circumferential groove or channel formed on an outer surface of the conical distal tip of the catheter, or wherein in a distal section of the loading coupler a diameter of the lumen tapers from the guidewire insertion end in a proximal direction to receive and direct a proximal end of the guidewire into the apparatus, wherein in a proximal section of the loading coupler the diameter of the lumen tapers from the catheter insertion end of the loading coupler in a distal direction to receive and couple with a correspondingly tapered distal tip of the catheter, wherein the tapered proximal section (110, 910) of the loading coupler includes a circumferential protrusion or rib formed on an inner surface of the loading coupler, the protrusion or rib configured for mating a circumferential groove or channel formed on an outer surface of the conical distal tip of the catheter, or the tapered proximal section (110, 910) of the loading coupler includes the circumferential groove or channel formed on the inner surface of the loading coupler, configured for mating the circumferential protrusion or rib formed on the outer surface of the conical distal tip of the catheter, and wherein in a middle section of the pliable loading coupler the diameter of the lumen is constant and wherein the straight middle section of the lumen connects the tapered distal and proximal sections of the lumen to straighten and stabilize the guidewire received from the distal section of the lumen prior to entry of the guidewire into the guidewire lumen of the catheter being held in the proximal section of the lumen; a longitudinally-extending area of weakness formed along a length of the pliable loading coupler; and a tab radially extending from the pliable loading coupler, wherein the tab is adapted to be gripped by a user in order to remove the pliable loading coupler from the catheter via the area of weakness.