What does "PO" indicate in medical orders?

• A. By nebulization
• B. By rectal administration
• C. By intravenous injection
• D. By mouth (oral administration)

Answer: (D)

PO indicates administration by mouth (orally). It tells you to give the medication to be swallowed in its regular oral form—such as a tablet, capsule, or liquid—rather than through another route like intravenous, rectal, or inhaled. The route matters because how the medicine is absorbed and how quickly it works depends on how it’s given. Some drugs must be taken with water, with food, or in a form that cannot be crushed, so following the PO instruction ensures the medicine is prepared and given in the intended way. If a patient can’t swallow, a clinician would choose a different route or formulation, since PO is specifically for oral administration.