What feature distinguishes a multiple-use vial?

A multiple-use vial is distinguished by the presence of preservatives that allow for multiple uses. These preservatives are crucial because they inhibit microbial growth, ensuring the vial’s contents remain safe for use over an extended period. This feature enables healthcare professionals to draw from the same vial multiple times, which can be advantageous in various clinical situations, such as managing medication shortages or reducing waste.

Other options do not accurately define the characteristic of a multiple-use vial. For instance, while it is true that some vials may be used for intravenous pushes, that specific use does not inherently denote whether the vial is single-use or multiple-use. Similarly, a vial designed for immediate administration doesn't imply it can be reused; immediate use may pertain to single-use vials. Lastly, the size of the vial does not determine its usage; a multiple-use vial can be the same size as a standard vial. Therefore, the defining characteristic is indeed the presence of preservatives in the vial, confirming its status for multiple uses.