What does the medical abbreviation p.o. stand for?

The abbreviation p.o. stands for "per oral," which is a Latin term meaning "by mouth." This term is commonly used in medical contexts to indicate that a medication or treatment should be administered orally, as opposed to other routes such as intravenous or intramuscular. It is crucial in clinical settings as it informs healthcare providers about the preferred method of medication administration, ensuring that treatments are delivered effectively and safely. The other options, while relevant in healthcare, do not accurately represent the meaning of the abbreviation p.o.