What does PRN (pro re nata) mean in medication orders? | Rounds What does PRN (pro re nata) mean in medication orders? | Rounds
Loading...

What does PRN (pro re nata) mean in medication orders?

Medical Advisory Board
All articles are reviewed for accuracy by our Medical Advisory Board.

Educational purpose only · Not a substitute for professional judgment or the full text of guidelines and labels.

Article Review Status
Submitted
Under Review
Approved

Last updated: July 14, 2026 · View editorial policy

PRN Medication Orders

PRN (Latin pro re nata) indicates that a medication is ordered as needed rather than on a fixed schedule.

The PRN instruction requires prespecified conditions for use, such as pain, nausea, or a specific symptom severity.

A PRN order should include documentation requirements for the indication, dose given, response, and reassessment time frame per local policy.

Common examples of PRN orders include short-acting analgesics for breakthrough pain and antiemetics for nausea.

Related Questions