P.r.n. - definition of p.r.n. by The Free Dictionary
Also found in: Medical
pro re nata (as the situation demands; as needed)
References in periodicals archive
In his clinical opinion, the inpatient use of a haloperidol p.
or equivalent was written on the prescription or the order was written in the p.
Once satisfactory analgesia is achieved, patients generally require less analgesia than when it is administered by P.