Abstract: A drainage device is provided for rupturing and draining the fluid contents of a flexible container, such as a dialysis drain bag. A pierce element is mountable in a use position in a waste disposal receptacle so as to engage a wall of a flexible container impaled on the pierce element to rupture the container and allow the fluid contents of the container to flow into the waste receptacle. The pierce element is mounted in a holder which is adapted to be stably mounted in the waste receptacle. In one aspect, an apertured receptacle has a base wall to which the pierce element is fixedly mounted to orient the pierce element in an upstanding position below an open end and within the sidewall of the receptacle. An optional inner wall may be carried within the receptacle and disposed concavely below the open end of the receptacle for supporting a flexible wall of a container in a position for rupturing by the pierce element which projects through the inner wall.