A system includes a vial access device including a spike, with the vial access device attachable to a first vial defining a first vial size, and an adapter transitionable between a shield position in which the adapter is attachable to the vial access device such that the adapter shields the spike of the vial access device and a vial position in which the adapter is attachable to a second vial defining a second vial size, the second vial size different than the first vial size.