A pen needle, comprising a reusable adapter configured for attachment to a distal end of a medication pen, the adapter having a proximal needle for accessing the interior of the pen injector and a fitting on the distal side for mating with a patient end needle assembly, and a disposable patient-end needle assembly having a base configured for mating with the fitting on the distal side of the adapter and a patient-end needle extending from a distal end of the base.