A hub for a single lumen or multi-lumen catheter is disclosed. In certain embodiments, the hub features integrated luers, and does not require the use of extension tubes or extension tube clamps. The hub has an actuating mechanism for closing fluid access to catheter lumens. In certain embodiments, the hub has a proximal and distal housing, and the proximal housing can be rotated, pulled or pushed relative to the distal housing for actuating the mechanism. In certain embodiments, the hub includes a valve, such as an iris valve, for opening and closing fluid access to lumens, or for regulating fluid flow rates through lumens. In certain embodiments, a switching element is used to open and close fluid access to hub lumens.
