An ostomy pouch includes a collection pouch having a first side wall and a second side wall connected to one another along a periphery, the collection pouch having a collection cavity defined between the first and second side walls, an outlet connected to and extending from the collection pouch, the outlet defining an internal passageway connected to the collection cavity, the outlet having a coupling element, and a drainage adapter configured to engage the coupling element so as to be coupled to the outlet. The outlet is foldable to a closed condition to close the collection pouch and unfoldable to an open condition to drain the collection pouch.