PRN; I know it stands for "as needed", but what do the initials literally stand for?

Question:

For example; "PO" translates into 'by mouth' but actually means "per oral".
Do the initials PRN actually mean something?
Thanx. Oh; & if so...in what language?

Answers:
The abbreviation for PRN is latin for Pro Re Nata.
Which means, as needed.

Pro re nata - Latin literally meaning "For the thing born," but commonly used to mean "as needed" or "as the situation arises."

Pro re nata - Latin literally meaning "For the thing born," but commonly used to mean "as needed" or "as the situation arises."

here is the link to wiki
http://en.wikipedia.org/wiki/pro_re_nata...

it's from latin:
prn (pro re nata) means "as needed"

Here is a site that gives you the scoop on prescription shorthand, and gives examples of the most commonly used notations:

http://arthritis.about.com/od/arthritism...

For a more in-depth look at prescription and other medical notations, check out this site:

http://arthritis.about.com/gi/dynamic/of...

PRESCRIBED (VIA) NURSING NOTES

PRN; I know it stands for "as needed", but what do the initials literally stand for?

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