What distinguishes external medications from other types?

External medications are specifically designed for application on the skin or mucous membranes, rather than being ingested or injected. This characteristic is what sets them apart from other types of medications.

The fact that external medications are not intended for swallowing indicates their unique application method and purpose. They are meant to be absorbed transdermally or to act locally on the surface tissues. This distinction is crucial in medication administration, as it influences how these medications are stored, administered, and monitored for efficacy.

The other options, while highlighting various aspects of medication or specific scenarios, do not accurately represent the fundamental nature of external medications. For instance, external medications can be stored, as long as proper guidelines are followed, and they are not exclusively for emergency situations or only for injection. Therefore, the understanding that they are specifically not meant for oral consumption and are generally stored separately aligns with their intended use and application in practice.