A flip-open multi-pack assembly (100) is provided which can contain a plurality of new pen needles, such as through the provision of a rectangular or tube-shaped shaped, hinged shell housing (102,104), wherein new pen needles can be stored in a plurality of user accessible openings each having a sterility barrier formed, for example, by covers that cover the non-patient end of the openings in which the new pen needles are contained. Used pen needles can be returned and stored in openings accessible by rotatably opening the shell housing. One or more of the openings within first and second opposite ends of the housing shell can be provided with a slidable internal holder within the device and are configured to releasably secure the inner shield of the new pen needle, and to then be pulled forward when the new pen needle is removed and lock at a forward position, and thereby create an interior space, accessible from an opposite end when the hinged housing is opened, for a used pen needle to be inserted and stored.
