In medication orders, what does the abbreviation PRN indicate?

• A. As needed
• B. Before meals
• C. Immediately
• D. Per routine

Answer: (A)

PRN means the medication is given as needed, not on a fixed schedule. It comes from the Latin pro re nata, meaning “as required.” In practice, you assess the patient’s current symptoms and decides if a dose is warranted within the safety limits and frequency set by the order. This is different from meds scheduled before meals or per routine, which are given at predetermined times, and from immediate or STAT orders, which require prompt administration for urgent conditions. When using a PRN order, you document the dose, time, and the symptom prompting administration, and you reassess the patient afterward to gauge effectiveness and monitor for side effects.