Which abbreviation refers to receiving medication orally?

The abbreviation that refers to receiving medication orally is "PO." This designation comes from the Latin term "per os," which translates to "by mouth." In medical contexts, PO is utilized to specify that a medication should be taken orally, allowing for an understanding that the medication will be absorbed through the digestive system. This route is commonly used for many types of medications due to its convenience and effectiveness in delivering systemic treatments.

Options such as NPO, which means "nothing by mouth," indicate the opposite situation and are used in contexts where a patient cannot eat or drink. Rx typically signifies a prescription or treatment plan rather than a method of administration, and T.O. usually stands for "telephone order," relating to how a prescription or instruction is communicated rather than how medication is administered. Thus, PO is distinctly the correct choice for indicating oral medication administration.