What Does prn Mean in Medical Terms?

prn stands for as needed (lowercase form). Latin pro re nata in lowercase charting.

Where you will see prn

You will most often see prn in medication orders and prescriptions, nursing notes, care plans and handovers.

Example

A medication order might be written with “prn” as shorthand for as needed (lowercase form).

Related abbreviations

• 1:1 — one-to-one observation
• 2g Na diet — two-gram sodium diet
• 3% saline — three percent saline (hypertonic)
• 4-point restraints — four-point restraints
• 5-FU — fluorouracil
• 6-MP — mercaptopurine
• 6-TG — thioguanine
• 7+3 — seven plus three induction

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